How JustAnswer Works:

  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.

Ask Jake Your Own Question

Jake
Jake, Technician
Category: Audi
Satisfied Customers: 2403
Experience:  Over 30 years experience, 17 years with Audi, Factory trained
9204914
Type Your Audi Question Here...
Jake is online now
A new question is answered every 9 seconds

I just bought a 2000 Audi A6 4.2 with OBD2 codes 441, 411 and

Customer Question

I just bought a 2000 Audi A6 4.2 with OBD2 codes 441, 411 and 423 and a slight rattle from the engine compartment at low rpm. I just bought an OBD2 connector to my computer to see if the codes disappear when I repair the car, which I planned to do myself. What do you think is the logical way to go about the diagnostics and repair these faults?
Submitted: 5 years ago.
Category: Audi
Expert:  JOHN replied 5 years ago.
ok 441 is a purge control incorrect flow alot of this is 95% vacuum leak so make sure to check all hoses very easy fix
Customer: replied 5 years ago.
What about the two other codes?
Expert:  JOHN replied 5 years ago.
411 is a evap leak large amount
Customer: replied 5 years ago.
I expected an answer to the hole question. This is it:

I just bought a 2000 Audi A6 4.2 with OBD2 codes 441, 411 and 423 and a slight rattle from the engine compartment at low rpm. I just bought an OBD2 connector to my computer to see if the codes disappear when I repair the car, which I planned to do myself. What do you think is the logical way to go about the diagnostics and repair these faults?

Optional Information:
2000 Audi A6 4.2 Quattro 4.2

Already Tried:
I bought a diagnostic cable between car and computer to see how the codes change as I repair the car. Haven't used the cable yet.

Test drove the car from NJ to Vermont and back and it drives normally.
Customer: replied 5 years ago.
Other expert please
Expert:  AudiDoc replied 5 years ago.
Ok, let me see if I can help.

P0441 - Evaporative Emission System Incorrect Purge Flow
P0411 - secondary air incorrect flow detected
P0423 - Catalyst Efficiency Below Threshold (Bank l)

In a lot of cases, I can look at a list of 3-6 codes, and maybe see one or two common causes, or possible failures that would trigger all of them. However, this may not be the case in your situation.

Let me break down the code descriptions even more:
441 - this means that as the fuel vapor purge valve is attempting to function, meaning purge fuel vapors into the intake manifold, the front oxygen sensors are not seeing a large deviation in the amount of oxygen in the exhaust stream.
411 - when you start the car cold, the secondary air system pumps air into the exhaust stream in order to heat the catalytic converters faster so that they become functional faster. While you're driving the car normally, at say 60mph steady-state, the engine computer runs a routine to start the 2nd air pump, and the computer watches for front oxygen sensor deviation to see if enough air is being pumped through the exhuast stream. If it doesn't sense this is happening, the check engine light gets turned on.
423 - the right catalytic converter is not in a good state of health, and this is likely the rattling noise you're hearing under the car.


Now, before I go a lot further, how confident are you that you can tackle both the EVAP problem and 2nd air problem? Either one will require some somewhat specialized tools.
Customer: replied 5 years ago.
Thanks so much AudiDoc, great answer. I repaired a lot of BMWs in the past, never Audis. I might buy the tools, which may I need?


Expert:  AudiDoc replied 5 years ago.
I can give you a much more thorough answer when I'm at my shop tomorrow, rather than at home, if that's ok.
Expert:  AudiDoc replied 5 years ago.
Ok, you're going to need to check the following items, and you'll need a hand held vacuum pump to perform these tests.

1) remove evap purge valve, also removing the two hoses connected to it. Apply vacuum to either end and see if it passes air. if so, replace the purge valve
2) the secondary air system is a bit more complicated, and will require a lot of vacuum hose testing.

I would need to go through my service information and try to find a secondary air diagram to assist you if you're considering tackling this problem
AudiDoc, Independent Audi Shop Owner
Category: Audi
Satisfied Customers: 6426
Experience: I've been working on Audis since I was 18 and own an independent Audi repair and performance shop
AudiDoc and other Audi Specialists are ready to help you
Customer: replied 5 years ago.
Ok, sounds good! I'm interested in tackling the problem. Please let me know the rest. Thanks for such good advice.
Customer: replied 5 years ago.
What do i do now?
Expert:  AudiDoc replied 5 years ago.
When I get to my shop this morning, I'll give up a vacuum diagram so you can start troubleshooting the 2nd air system
Expert:  AudiDoc replied 5 years ago.
Ok, what you're going to need to do is follow the small vacuum lines from the combi-valves on the backs of each cylinder head. They will join in a "y" and then connect to a solenoid valve. Pull the line off the solenoid valve, and apply vacuum to it, make sure it holds. If not, check valves and fittings for leaks. If you don't find the problem here, you're going to have to trace back from the solenoid valve, and continue backtracking on the vacuum line until you're completely sure there are no vacuum leaks.

You're also going to have to energize the secondary air injection pump and listen for audible air leaks from the corrugated plastic pressure hoses.

If you're satisfied the both of these tests work, then it's likely that your combi-valves are carboned up and are not allowing air into the exhaust stream, or it could be as serious as carboned passages in the cylinder head itself, however this is more common with BMW v8's than Audi v8's.
AudiDoc, Independent Audi Shop Owner
Category: Audi
Satisfied Customers: 6426
Experience: I've been working on Audis since I was 18 and own an independent Audi repair and performance shop
AudiDoc and other Audi Specialists are ready to help you
Customer: replied 5 years ago.
Hi AudiDoc,
Thanks for the excellent description.
First off, I tested the purge valve. It leaks slightly, but only backwards -from engine to tank. I'll relplace it anyway and see if it helps.
In regards XXXXX XXXXX air there was one BIG leak. There are two y connectors on the line right next to the non return valve before the solenoid valve line and the change over valves at the front.
One of those y connectors has a line to the vacuum reservoir and the other y connector had a line just dangling open down by the vacuum reservoir.
I plugged it with a screw and now all the lines hold tight and the vacuum stays. So I've obviously been driving With no vacuum at all for those components... An important question is of course where is the open line supposed to be connected to?
I started the engine with the plugging screw in and it still runs ok. Measured the vacuum with engine on. Looks steady and stays after you turn off.

I bought an obd2 cable but it didn't work with the computer computer. Do you recommend any diagnostic tool? vag-com?

Lastly, I would like to ask how difficult it usually is to change the catalytic converter on bank 1? That one is obviously broken and rattling.
Customer: replied 5 years ago.
The vacuum line at the front where I wrote change over valve I think actually is for intake manifold flaps or something like that. Strangely, one of them is connected directly to the vacuum after the one way valve and the other one is connected to a vacuum solenoid. Shouldn't both sides be connected via the vacuum solenoid valve?
Expert:  AudiDoc replied 5 years ago.
As these cars are somewhat rare, and I only get them in the shop on occasion, the routing of all of these lines aren't completely ingrained into my head as they are on 2.7/2.8 v-6's. Any possibility you could get a picture of these and upload them here?
Customer: replied 5 years ago.
I bought my own ODB-2 reader yesterday and got all new codes!
P1141
P1423 (sec air inj bank 1 too low flow?)
P1411(same on bank 2?)
P0455 (large evap leak?)

On this link you'll find the pictures: http://web.me.com/tacksya/Site/Last_Viewed_Event.html

Thanks/Olle
Expert:  AudiDoc replied 5 years ago.
Olle...I'm sorry, but that page you posted...can you please recheck the address? It's not showing up for me at all, and I'm hoping that, between a couple of detailed pictures, and those fault codes, I can help you along.
Customer: replied 5 years ago.
Expert:  AudiDoc replied 5 years ago.

Ok, let's go down the detailed code list again:

P114117549Load Calculation Cross Check Range/Performance

P142317831

Sec.Air Inj.Sys.,Bank1 Flow too Low

P141117819Sec.Air Inj.Sys.,Bank2 Flow too Flow

P0455 16839 - EVAP system large leak detected

 

Now, from these and your pictures, it still sounds like you have a major vacuum problem, however without seeing the big picture, meaning a good detailed picture of your engine compartment with all covers off, it's still somewhat difficult to see if anything is out of place, and obviously it is, since all of the vacuum lines need a source and a component it works upon. There should be some vacuum solenoid valves that have an electrical connector and vacuum lines connected to them as well as a series of vacuum tees and check valves all over the rear part of the engine above the intake manifold. I would want to see these as well. Again, not trying to be a pain, but the 4.2 ART engine code is a fairly rare one, so memory doesn't serve very well in this case.

 

Customer: replied 5 years ago.
Hi AudiDoc,
On the following site you will find overview and behind engine pictures.
http://web.me.com/tacksya

click on:
Last Viewed Event 2

/Olle


Expert:  AudiDoc replied 5 years ago.
Olle....I'll get a look as soon as possible, but I've got a shopful that need to be cleared out before I go home. I do have service information that I need at my house, so I'll take a look when I get there, after a bit of grilling :-)
Customer: replied 5 years ago.
Hope you enjoyed the grilling!
Curious and can't wait to hear your findings. Earlier you asked me to activate the   air injection pump. Should I connect it directly to th battery?
Customer: replied 5 years ago.
It holds vacuum now in the secondary air and intake flap vacuum unit lines. I took off the left rear wheel liner and checked vacuum to the evap test pump. When you start the engine it gets vacuum but doesn't hold. Seems to be a leak somewhere.

I reset the check engine light and have test driven it to full warm up twice since. Has not yet come on again.


Expert:  AudiDoc replied 5 years ago.

What exactly do you mean the vacuum doesn't hold at the LDP vacuum supply line.

 

Meaning, if you remove the vacuum hose that goes to the intake, and put a vac gauge on it, what happens?

Customer: replied 5 years ago.
With the vacuum gauge connected, I started the engine and got a vacuum reading at the LDP supply line. When I turned engine off, the vacuum went down to zero.

I don't know where to find the LDP vacuum hose in the engine bay.

But, with the vacuum gauge connected at the open line from the T connection in front of the engine where it branches out to the reservoir, secondary air etc, the vacuum holds after I switch off the engine
Expert:  AudiDoc replied 5 years ago.
Ok, good, then it sounds like everything is normal. The only time you see vacuum at the LDP is when the engine is running. This is a straight shot right to the intake manifold. I believe towards the front of it on the left (driver's) side, but the last one I worked on was an A8, so the engine code itself isn't an ART as you have. It should still be similar. It's a fairly large pipe, maybe 6-8mm diameter?

So, right now, is everything else functioning correctly? Have you put enough miles on it to determine if any of these codes come back?
Customer: replied 5 years ago.
Then there is the open line that i have plugged with a screw. It is the thin braided hose from the T connections. It comes out on the drivers side front of engine next to the hose going to the vacuum reservoir.

Haven't put enough miles on it yet. How many miles do I need?
Customer: replied 5 years ago.
The MIL came on after aXXXXXyesterday. I checked codes and got 1: P0432 (catalyst bank 2 below threshold?). I got one system not ready: o2 Sensor.
EVAP and secondary air said are ready.
Expert:  AudiDoc replied 5 years ago.

Let me do a bit of thinking again, and I'll get back with you when I get into the shop

Customer: replied 5 years ago.
Any ideas?
Expert:  AudiDoc replied 5 years ago.
I'm still curious about that plugged vacuum hose, although I would doubt that that is causing the codes that you're seeing. The pictures are very good, although without the car right in front of me, it's still difficult to determine that hose routing.

However, let's move onto the next codes.

The oxygen sensor code...which bank is that? What's the actual code?
Customer: replied 5 years ago.
oxygen sensor is not yet a code, just "Not ready: 02 sensor"
Expert:  AudiDoc replied 5 years ago.

Still going to need more drive time before:

1) the monitor sets

2) and when it attempts to set, if there is a fault, determine if the sensor is on the same bank as the cat problem.

 

Usually O2 monitors are done on steady-state 60 mph/2300 rpm drives without a lot of throttle movement.

 

If you had a factory scan tool or vag-com, the test can be done within 5 minutes without the car moving anywhere.

Customer: replied 5 years ago.
Did a long drive yesterday and 02 sensor still not ready.
I got three error codes:
P1141
P0432
P0441
What do I do now?
Expert:  AudiDoc replied 5 years ago.

Ok, first, the code list and descriptions

 

P114117549Load Calculation Cross Check Range/Performance

P043216816Main Catalyst Efficiency Below Threshold Bank 2

P044116825

Evaporative Emission System Incorrect Purge Flow

 

Wow...this seems to be a cyclic problem, and it seems as though it's related to one.....*possibly* two problems. First thing to take care of the the 1141 and 441 codes. They may be related. Have you checked your EVAP purge valve? This valve lives on top of your airbox, and has a two wire harness connector with a rubber hose on each side of the valve. Remove this valve and see if a vacuum pump holds vacuum on either side of it.

Customer: replied 5 years ago.
Hi Audi Doc,
This is the same answer you first gave me on March 17 and yes I tested the purge valve. It holds vacuum toward the engine. You can pull air toward the tank it if you apply a lot of vacuum. Should I change it?
Expert:  AudiDoc replied 5 years ago.

Olle, you're absolutely right. I've got to admit, there's a lot of information that has gone back and forth here, and I overlooked my previous response.

 

I can't say for sure that this is the problem. This is especially true, since the purge valves can be finicky, meaning they can sometimes stick in the open position, but not always. This can be ambient temperature dependent as well. Still, it shouldn't pass any air either way if it's not energized.

 

I'm thinking that I'm starting to reach the end of my long-distance, through-the-computer screen diagnostic ability on this one. A problem like you're experiencing would be tough enough to tackle with the car right in front of me, and it's starting to get darn near impossible online.

 

I do appreciate the two accepts and the bonus you've previously authorized. Would you like me to see if I can opt out and possibly get another expert involved who may have a different strategy?

Customer: replied 5 years ago.
If you think someone Can solve it, sure pass it on to another expert. Thanks for all your help /olof
Expert:  AudiDoc replied 5 years ago.
No problem at all. I'll go ahead and opt out, and send a message to a couple of guys on here who may have a different strategy.
Expert:  Jake replied 5 years ago.

Hello,

 

Thank You for choosing Just Answer for your query. Yes, I can help you.

 

Audi Doc asked me to look into this and see if I could assist you. I can't afford to get as "Involved" as he had, but if you "Accept" as you feel you have gotten valuable information I will continue to do answer if I have further input as certain conditions are beyond the scope of this forum and pay structure.

 

 

I previously owned an 02 A6 4.2 and work on MANY. First off I can see the intake manifold assembly has failed and requires replacement. In your photo I can see the two vacuum motors are stuck in the "activated" position. These control the intake runner lengths within the manifold. They should be deactivated when the vehicle is shut off and activated when you start the vehicle and idle. You can check and you will find both levers that go into the manifold are seized. This is very COMMON on the 2000 year model 4.2s only. I have replaced about 8, and only on the 2000s. They retail for about $1,800 and about 3 hours to replace.

 

The P0441 EVAP code is typically the purge control valve, I would just go ahead and change it as they often work intermittently.

 

I need to see the Measuring block #32 values. This needs to be scanned after running the vehicle for some time and BEFORE you clear any stored Diagnostic Trouble Codes (DTCs). When you clear the codes, it resets the fields to 0%.

 

P0432 - The catalyst has likely failed. I suggest you clear the code, correct the other conditions and see if it comes back, as other conditions can effect it, but typically not. Also, be sure to run premium grade fuels as required. Mid grade is OK once in awhile, but not regularly.

 

In your images I can not see the vacuum hose you have plugged. I see the two running from the left front of the head to the side of the vehicle, but I do not see the plugged one. There should be NO FREE vacuum hoses, so I must see which one is now "plugged". Can you send a image of the plugged hose, or at least of where the other end goes?

 

I hope that I have answered your questions and addressed your concerns. Should you have any further questions for me, please do not hesitate to ask. I want you to be 100% satisfied with my answer.

 

Positive feedback and bonuses are always appreciated! If you accept my answer please click on the "ACCEPT" button by THIS answer.

 

Thank You!

Jake "The Audi Doctor"

Jake, Technician
Category: Audi
Satisfied Customers: 2403
Experience: Over 30 years experience, 17 years with Audi, Factory trained
Jake and other Audi Specialists are ready to help you
Customer: replied 5 years ago.
Thanks for the advice Jake!
Main short term objective is to get the car inspected. Moved it to NJ and we cant get it inspected here now with these codes.
Not sure I can afford a new manifold. What happens if I just lubricate and try to get the shafts and activators moving again? Does the manifold affect DTC?
I ordered a purge valve as you recommended.
What is measuring block 32?

The plugged hose in the picture is the one of the two parallel ones in front of the engine left side. One goes to the reservoir and the other is plugged. They come from the T connections between manifold actuators solenoids and the hose going backwards towards the secondary air vacuum solenoid.

Expert:  Jake replied 5 years ago.

Hello,


Not sure I can afford a new manifold. What happens if I just lubricate and try to get the shafts and activators moving again?

 

Won't work, I've tried. You would have to take the manifold apart and clean and lubricate or replace the bushings. The bushings and seal are not avilable seperatly you would have to come up with your own solutions. I have taken them appart and looked into it, but it would be too time consuming for me to do so. If you had lots of time...

 

 

Does the manifold affect DTC?

 

Not typically, just performance and possibly MPG.

 


I ordered a purge valve as you recommended.

 

That usually takes care of it.

 


What is measuring block 32?

 

Fuel trim data. Here is an article I copied off of the Ross-tech site the leading aftermarket VW/Audi scanner company. Andy doe s a very good job of explaining trims and ch #32.

Fuel Trim Info

From Ross-Tech Wiki

Understanding Fuel Trim

Some of the most common Fault Codes (DTC's) pertain to fuel trim (rich mixture, lean mixture, etc.) Here is an explanation of fuel trim and what it does for us. The ECU controls Air/Fuel mixture in order to maintain power, efficiency, and emissions. A/F is expressed as either a ratio (14.7:1 for example) or as a Lambda value. With iso-octane ("ideal" gasoline), Lambda of 1.0 is equal to 14.7:1 A/F. This is known as "Stoichiometric", a condition where there is a perfect balance between oxygen molecules and the various hydrogen and carbon based molecules in petroleum. With the oxygenated gasoline that most of us use, actual A/F ratio of 15:1 is closer to stoichiometric.If Lambda is greater than 1.0, then there is a surplus of air and the engine is running lean. If Lambda is less than 1.0, then there is a surplus of fuel and the engine is running rich. It should be noted that the ratios are mass-based, not volume-based.

So, why don't we always run at 1.0 all the time? Well, we do MOST of the time. At cruise and idle, mixture is held tightly to 1.0 to keep the catalytic convertor at optimal efficiency, so the emissions are minimized. However, when we need acceleration, the mixture gets richer. Why? Maximum power is made between 0.85 to 0.95 Lambda (12.5 to 14.0 A/F with iso-octane). So, under acceleration, mixtures get richer. Sometimes you want to get even richer under acceleration to keep detonation (pre-ignition of the mixture from excess cylinder temperatures) away. The 1.8T has a relatively high compression ratio for a turbocharged engine, which especially under lots of boost, is very succeptible to detonation).

So, now that we know that the ECU wants to be able to control the A/F ratio. It has a prescribed set of values (maps) for a given RPM, Load, etc. So, the ECU tells the injectors to pulse for exactly XX.X milliseconds and that SHOULD get us the proper A/F ratio that we want. Well, if you tell an employee to go do something, you want to make sure they actually did it, right? The ECU has some snitches (the front O2 sensor and the MAF, for the most part) that will report back whether or not the desired mixture has been attained. The rear O2 sensor is used mostly to monitor the condition of the catalytic convertor, although in some applications it also contributes to trim information.

Based on feedback from the snitches, the ECU learns to apply a correction factor to its commands to the fuel injectors. If you know that your employees take longer than the standard allotted time to do a specified job, you will need to adjust for that in your planning (injectors are in a union, so it is tough to fire them ). The learned values go between the maps in the ECU's Flash ROM (the "chip") and the signal to the fuel injectors. These learned compensations are known as "trim". So, when you see "trim", it means "compensation".

"Add" means additive trim, which is addressing an imbalance at idle. When the ECU is using additive trim, it is telling the injectors to stay open a fixed amount longer or shorter. The malfunction (e.g. vacuum leak) becomes less significant as RPM increase. For additive adaptation values, the injection timing is changed by a fixed amount. This value is not dependent on the basic injection timing.

"Mult" mean multiplicative trim, which is addressing an imbalance at all engine speeds. The malfunction (e.g. clogged injector) becomes more severe at increased RPM. For multiplicative adaptation values, there is a percentage change in injection timing. This change is dependent on the basic injection timing.

You can check your current state of trim by using VAG-COM or equivalent to look in Group 032 (in many modern ECU's, consult your Factory Repair Manual for the specific group for your particular vehicle) in your engine measuring blocks. The first two fields will have percentages. The first field tells the fuel trim at idle (Additive). The second field tells the fuel trim at elevated engine speeds (Multiplicative). Negative values indicate that the engine is running too rich and oxygen sensor control is therefore making it more lean by reducing the amount of time that the injectors are open. Positive values indicate that the engine is running too lean and oxygen sensor control is therefore making it richer by increasing the amount of time that the injectors are open.

It is totally normal for both the first and second fields to be something other than zero. In fact, zeros IN BOTH FIELDS indicates that either you just cleared codes (which will reset fuel trim values) or something isn't working properly. If values get too far away from zero, it will cause a DTC (fault code) and can set off the MIL (commonly referred to as the Check Engine Light, or CEL). Specifications for normal operation are usually somewhere near +/- 10%.

In general, an out-of-spec value in the first field (Additive) indicates a vacuum leak since it is mostly present at idle, when vacuum is highest. An out-of-spec value in the second field (Multiplicative) indicates a fault at higher RPM, and may point to a faulty MAF.

Here's a good sanity check for the status of your MAF. Do a full-throttle run all the way to redline in a single gear (second works fine). Group 002 usually shows air mass in g/s (in many modern ECU's, consult your Factory Repair Manual for the specific group for your particular vehicle). Your peak airflow should be roughly 0.80 times your horsepower. So, if you have a stock 150 hp 1.8T, expect around 120 g/s. If you see significantly less than that, you MAF may be on the way out. This still works if you are chipped, but "race" programs may make more power through timing, rather than airflow. Therefore, take all readings with a grain of salt.

Andy 10:45, 26 January 2006 (Eastern Standard Time)



The plugged hose in the picture is the one of the two parallel ones in front of the engine left side. One goes to the reservoir and the other is plugged. They come from the T connections between manifold actuators solenoids and the hose going backwards towards the secondary air vacuum solenoid.

 

I do not have another 4.2 to look at right now. I need a better discription of exactly where the plugged hose comes from, or a picture of the hose (the end that is hooked up) to further assist you. If I get one in in the mean time I will let you know where it should go.

 

Thank You!

Jake

Jake, Technician
Category: Audi
Satisfied Customers: 2403
Experience: Over 30 years experience, 17 years with Audi, Factory trained
Jake and other Audi Specialists are ready to help you
Customer: replied 5 years ago.
Hi Jake,
I have now replaced the purge valve and put on new hose clamps
Here is the picture of the T connectors at the vacuum hoses.

http://web.me.com/tacksya/Site/Last_Viewed_Event_3.html

The front/left T with the tattered hose goes to the reservoir. The rear/right T goes to the plugged (formerly open) hose. It ends next to where the reservoir hose connects to the plastic tube of the reservoir. The rear hose on the rear T goes back over the engine to the secondary air solenoid valve.

Let me know where you think it should go.

I bought the vag-com cable. Will try to install the software and see if I can give you measuring block 32

Thanks/Olle



Customer: replied 5 years ago.
Hi again Jake,
I cleared the code and did a 1 hr test drive now with the new purge valve installed. The EVAP code is gone and vag-com says passed or ready or whatever it's called on all tests, even o2 sensors.

The reamaining fault codes are:
P1141     17549     Load Calculation Cross Check Range/Performance
P0432     16816     Main Catalyst Efficiency Below Threshold Bank 2

I can't read measuring block 32. I bought the VAG com license today, hope to get the key so I can use it tomorrow.

Thanks! /Olle

Expert:  Jake replied 5 years ago.

Hello Olli,

 

I have a 4.2 A6 scheduled in for the middle of the week and will check the vacuum line routing. If you can get back to me with that MVB #32 data it could be quite helpful on the #17549 DTC.

 

note: be sure NOT to take your MVB #32 readings after erasing the fault memory as this resets all fields to 0%.

 

Jake

Customer: replied 5 years ago.
Jake,
Here are the MVB 32 results: 2.4% 3.1% 2.1% 2.3%
Expert:  Jake replied 5 years ago.

Those are all within normal operating tolerance (+4.0% to -4.0%). I will look into the 17549 and the vacuum routing when the other 4.2 comes in and get back to you. If you monitor the ch# XXXXX reading periodically (without erasing the codes) and it goes out of tolerance range let me know.

 

Jake

Jake, Technician
Category: Audi
Satisfied Customers: 2403
Experience: Over 30 years experience, 17 years with Audi, Factory trained
Jake and other Audi Specialists are ready to help you
Customer: replied 5 years ago.
Thanks. I look forward to hearing the vacuum routing when you have that. did you see the pictures that I sent you in the last link?
Expert:  Jake replied 5 years ago.

Hello,

 

Yes I received the picture, but it is unclear to me. I will check the "live" vehicle so I can be sure.

 

Thank you!

Jake

Expert:  Jake replied 5 years ago.

Hello,

 

I looked at the 4.2 and the vacuum lines should be routed as follows;

 

The two lines coming from the left fender both run parallel to the front of the left cylinder head. They both pass behind the timing belt cover through the space between the cylinder head, block, and timing cover. They both "T" into the same vacuum line at the left front of the intake manifold. They are side by side( T T) into the same line. They T into the line that runs from the solenoid valve mounted on the fuel rail on the left rear of the motor. This valve when opened supplies vacuum to the combi valves for the secondary air injection. It is VERY common for this line to shrink and become disconnected causing a secondary air flow insufficient Diagnostic Trouble Code (DTC). The other end of the line (on the other side of both Ts) goes to the intake manifold, it's source vacuum. This is also the source for both solenoid valves that activate the "manifold plane" vacuum motors.

 

Let me know how this compares.

Thank You!

Jake

Jake, Technician
Category: Audi
Satisfied Customers: 2403
Experience: Over 30 years experience, 17 years with Audi, Factory trained
Jake and other Audi Specialists are ready to help you
Customer: replied 5 years ago.
My lineup around the engine is exactly lie your describe. If you had read my earlier questions you would have seen I had secondary air code that disappeared since I got the vacuum back in the system plugging the open line by the driver side fender

One of these two parallel lines goes to a thin plastic tube that goes to the reservoir in the driver side fender, routed like you describe between block and timing cover.

I understand by your answer the other one goes to the fender.
The big question remains: Where do I connect it to?

I would appreciate a quick answer since I need to get the car inspected before our road trips in the coming weekends

Thanks! /Olle
Expert:  Jake replied 5 years ago.

Hello,

 

I did not understand by your previous posts that the line going to the fender was the one disconnected and plugged going towards the fender. I thought you were describing at the engine end of the line. I will look into it further, but in the mean time this should NOT effect any check engine light or storing of any codes so long as the source of vacuum (engine side) is plugged. It is likely a vacuum supply to the climate control or something? I am not sure. Only the 4.2 has the two lines here. Other models have only the one going to the reservoir. Have you removed the inner fender and inspected it?

 

I will also check into the #17549 your main point of contention I assume. This is not a common DTC, it will take a bit of "looking" into. Sorry if i can;t get to it ASAP, I will do what I can.

 

 

Thank You!

Jake

Customer: replied 5 years ago.
Do you think the 17549 has anything to do with the previous "o2 sensors not ready" message? It's gone now but it's been there. Or with the non connected vacuum?
Customer: replied 5 years ago.
I ordered a MAF sensor just in case. Might help?
Expert:  Jake replied 5 years ago.

Hi,

 

Sorry I typed out a response yesterday to the first reply and "lost" it and didn't get back to it.

 

I do not think the previous "O2 sensors not ready" would have anything to do with it. What?where was that message?

 

The 17549 is typically associated with the MAF, throttle body or vacuum leak. The thing is the MVB #32 values do not indicate any problem with any of those components. It would be a good idea to try a MAF if you ordered one. Be sure and check the #32 values periodically and definitely any time before clearing any DTCs.

 

I did run across something (not personnaly) on a 4.2 A8 where the tech disconnected the kick down switch on the throttle cable and the 17549 did not return. This being a 2000 year model (1st year) does it have a throttle cable? Or is it "Fly by wire" like the 2001<?

 

The 17549 is likely NOT associated with the plugged vacuum line as the vacuum (engine) side is plugged.

 

What type os VAG-COM do you have? You may be able to clear the DTCs, force the system to set readiness codes (all monitors pass), then get your certification ASAP.

 

There is ALLWAYS the possibility that the intake manifold is the cause of the 17549 as it is related to the load signal. Though I could not give you a factual specification link. It would be best if the manifold could be replaced and see if that cleared it. Possibly you could try moving the flaps all the way to one position or the other and seeing if either setting changes the DTC status.

 

Let me know how it goes.

Thank You!

Jake

Customer: replied 5 years ago.
I have 409.1. Would be happy to upgrade if I can clear force readiness. Do you know?
Customer: replied 5 years ago.
I just found the tube at the fender and connected the vacuum hose to it. Also put on the new air mass meter.
Customer: replied 5 years ago.
Jake,
The air mass meter and the vacuum hose did the job. The only code that remains now is the catalyst. I ordered a new one. I think we're done for this time. Thanks for your insights! /Olle
Expert:  Jake replied 5 years ago.

Good deal! It was likely the MAF sensor.

 

Did you ever try moving the manifold flap positions?

 

Did you order a factory catalyst? I suggest you only use Original Equipment Manufacturer (OEM). If you use an aftermarket catalyst they tend to fail in short order. Sometimes less than on year.

 

Thank You!

Jake

JustAnswer in the News:

 
 
 
Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.
 
 
 

What Customers are Saying:

 
 
 
  • I would (and have) recommend your site to others I was quite satisfied with the quality of the information received, the professional with whom I interacted, and the quick response time. Thanks, and be sure that I'll be back whenever I need a question answered in a hurry. Stephanie P Elm City, NC
< Last | Next >
  • I would (and have) recommend your site to others I was quite satisfied with the quality of the information received, the professional with whom I interacted, and the quick response time. Thanks, and be sure that I'll be back whenever I need a question answered in a hurry. Stephanie P Elm City, NC
  • used your service this weekend with "Trecers" help. thank you ,thank you, thank you. replaced an A/C fan motor. Local Auto Zone had part. $15.00 "tracer" fee and $40.00 for parts, I saved several hundreds of dollers at a shop. i will recommend you and use you in the future. David L. Richmond, TX
  • 9 dollars, 2 hours of my time, and I drove away. Your diagnosis was right on the mark. Thank you so much. Phil Marysville, CA
  • Lurch. Thank you very much. I had real doubts about this website but your promptness of response, quick followup and to the point answer with picture was incredible. Charles Walnut Creek, CA
  • As a single woman, I really appreciate an excellent and affordable opinion.
    Thank you Geordie, I will not hesitate to contact justanswer in the future!
    Sue Charleston, WV
  • Another great insight to what may be the problem. I will have my mechanic take a look at it tomorrow. Thanks again, Frank...you do indeed know your stuff. Jim Castleberry, FL
  • Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help. Mary C. Freshfield, Liverpool, UK
 
 
 

Meet The Experts:

 
 
 
  • AudiDoc

    Independent Audi Shop Owner

    Satisfied Customers:

    1681
    I've been working on Audis since I was 18 and own an independent Audi repair and performance shop
< Last | Next >
  • http://ww2.justanswer.com/uploads/audidoc/2008-12-23_175252_headshot.jpg AudiDoc's Avatar

    AudiDoc

    Independent Audi Shop Owner

    Satisfied Customers:

    1681
    I've been working on Audis since I was 18 and own an independent Audi repair and performance shop
  • http://ww2.justanswer.com/uploads/35/350matt/2012-6-7_182356_matsavatr.64x64.jpg Matt's Avatar

    Matt

    Engineer

    Satisfied Customers:

    461
    Mechanical Engineer with 20 years experience in the auto industry, 8 yrs in formula 1 engine testing
  • http://ww2.justanswer.com/uploads/MI/mikeamechanic/2013-4-2_175558_photo.64x64.JPG Mike Kelly's Avatar

    Mike Kelly

    Audi Mechanic

    Satisfied Customers:

    259
    17 years experience as a auto mechanic, foreign and domestic.5 years running my own repair business.
  • http://ww2.justanswer.com/uploads/FourRingsTech/2010-01-26_135603_GetAttachment.jpg Michael Miller's Avatar

    Michael Miller

    ASE Certified Technician

    Satisfied Customers:

    241
    ASE Master Technician. Audi certified, including R8 and TDI (clean diesel).
  • http://ww2.justanswer.com/uploads/NA/nabilc/2011-1-24_205715_jap500.64x64.jpg Billy's Avatar

    Billy

    Trainer/Master tech.

    Satisfied Customers:

    229
    Trainer 8+ years, Master tech. 10+ years, SAE member
  • http://ww2.justanswer.com/uploads/tsmodie/2009-6-10_144056_tim.jpg Tim Mohr's Avatar

    Tim Mohr

    ASE MASTER TECH

    Satisfied Customers:

    204
    30 YRS EXPERIENCE, FOREIGN AND DOMESTIC, GAS AND DEISEL
  • http://ww2.justanswer.com/uploads/CA/caprio23/2011-12-13_155550_20111213105344.64x64.jpg Anthony's Avatar

    Anthony

    ASE Certified Technician

    Satisfied Customers:

    174
    ASE Master Automobile Technician with over 20 years exp. in this field.
 
 
 
Chat Now With An Audi Mechanic
Jake
Jake
Audi Mechanic
2403 Satisfied Customers
Over 30 years experience, 17 years with Audi, Factory trained