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Roman, Technician
Category: Audi
Satisfied Customers: 556
Experience:  over 20 years vw audi and porsche technical repair
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Audi A4 Quattro Avant: I have an Audi 2002 A4 3.0 quattro,

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I have an Audi 2002 A4 3.0 quattro, and I have an issue where when I accelerate while on a hill or slight incline (when in any gear, in drive or tiptronic mode, but especially in drive) I get a little fluctuation in RPMs (2000 will drop to 1800, and back and forth like the ticking of a clock) and a stuttering, shaking, or trembling feeling coming from the car. When on the highway for a few miles, doing this will trigger 3 DTC faults:

In Engine DTC block:
01057 - Function: Constant Voltage Charge
01073 - Clutch Pressure System

In ABS DTC block:
01119 - Gear Recognition Signal

What should I do? What is the problem?
Hello ,
Here to answer automotive questions and make you feel comfortable and become familiar with your product.

can you try to clean the throttle body, clear the codes and reset the throttle angle, then go for a test drive and re check the faults then let me know how you make out after that has been completed.
Customer: replied 3 years ago.

Can you direct me to a video or literature on the process, especially as it relates to the angle. I am mechanically inclined, a tinkerer, a jack-of-all, but lost under the hood of the Audi A4.

Customer: replied 3 years ago.

Also, I was suspecting something wrong with the transmission: ATF levels, torque convertor issues, etc. Was I mistaken? Do these codes tell you something is wrong elsewhere (i.e. throttle body)?

You must use vag com software to perform this procedure.

This procedure must carried out before suspecting any transmission problems when there are not any faults present. Let me know what you find and we will continue the diagnosis of your vehicle

This procedure details how to perform a Throttle Body Alignment (TBA) on many VW/Audi vehicles. This procedure cycles the motorized throttle body through various states (idle, part throttle, WOT) to relearn their positions. Some examples of reasons to perform a TBA:

The vehicle's battery has been disconnected and re-connected
The ECU has been removed and reinstalled
The Throttle Body has been cleaned or removed and reinstalled
The Accelerator Pedal has been removed and reinstalled

In some vehicles, the car will not run correctly, or may not run at all without performing a TBA after one of the above operations. The TBA can be performed on both Drive-By-Wire (DBW or E-gas) as well as Cable-throttle cars as long as there is no Idle Stabilization Valve (ISV). If there is an ISV, then there is no motorized control of the throttle at all. Typically, '96-'99 VW/Audi have motorized Cable-throttle, and '00+ VW/Audi have DBW. Obviously, there are some exceptions. This should be obvious but TDI's do not have throttle bodies.
There are certain test conditions that must be met before doing a TBA:

No DTC's in the Engine Controller
Battery voltage at least 11.5 V
Throttle must be at idling position (keep your foot off the gas pedal)
Throttle body part must not be dirty (carbonized).
Coolant temperature must be between 5 and 95C
If fault codes were cleared cycle the ignition off and back on prior to running Basic Settings.

Procedure for performing a Throttle Body Alignment on DBW Cars using KWP-2089:
(Check to see if the engine speaks KWP- 2089 by looking in the top left of the Open Controller Screen Some examples of KWP-2089 engine controllers are 2002+ Audi A4, 2002+ VW Passat, and Touareg)

Turn the key on but do not start the car.

[01 - Engine]
[Basic Settings - 04]
Group 060
It should say "Basic Settings: OFF" on the top of your screen.
Click [ON/OFF/Next] to turn on Basic Settings.
It should now say "Basic Settings: ON" on the top of your screen.
Once you do this you will see the top right display say ADP RUN. The TB adaptation is being done as soon as you switched basic settings on. You will see the values change and hear the TB cycle for the first few seconds then it will stop. Leave it in Basic Settings for about 30 seconds.
Click [ON/OFF/Next] to turn off Basic Settings.
It should now say "Basic Settings: OFF" on the top of your screen
Click the [Done, Go Back] button and you're all set.

Be sure not to touch the accelerator and make sure the engine is NOT running when you do this!

Customer: replied 3 years ago.

OK, I both cleaned the throttle body and aligned it today. It was a little gunky, and cleaning it may have improved responsiveness and idling minimally; however, the problem still persists. If I accelerate up a 5-10 degree incline, and tiptronic's in drive and in 5th and going about 40mph, the car makes a strange variance in rpm from about 1600 to1450 back and forth as long as I am pressing the gas pedal to sufficiently maintain 40mph up the hill. Also, as I start up a 20 degree hill from a stop, if I accelerate pretty hard (not pedal-to-the-medal hard, but an aggressive acceleration nonetheless) by the time I approach 20-30 mph, I feel a strange rumbling feeling (like I described earlier) that will stop as soon as I stop accelerating. I cleared the other DTCs, and I haven't driven it enough to trigger any more DTCs. What's next?

That is good, cleaning and adapting the throttle was well needed. Although now we have to see which if any DTC's return.

This just states there is a fault logged in the TCM
01119 - Gear Recognition Signal
Can you check the transmission control module to what the logged fault is???

16805/P0421/001057 - Warm Up Catalyst; Bank 1: Efficiency Below Threshold
16815/P0431/001073 - Warm Up Catalyst; Bank 2: Efficiency Below Threshold

This fault states to replace the failed catalytic converters.
Eventually they need replacement before state inspection is required.

Please let me know the logged fault in the TCM

Customer: replied 3 years ago.

I remember checking the transmission (02) for DTC when the CEL was on the other night, it said none were present. Could the cats be causing this? The car has 116000 miles on it, and it is the v6 3.0L.

no the cats fail over time.

Continue to drive and re check again in another day. The dtc will log again once the TCM notices there is a fault. Also the check the ABS module for a logged fault.

Check to see if the carpet is damp or wet on all compartments

There is a sensor under the rear seat bench for the ABS which sends a signal telling the transmission when the ABS is working. They need to communicate with one another.

At times this sensor fails and does not leave any fault except the one you have stating to check the TCM for faults and there are none logged. The fault lies in the accelerometer sensor under the rear seat bench. We replace this sensor, set steering angle basic settings then go for a road test this usually solves the problem with the trans issue.
Customer: replied 3 years ago.

My carpet is dry, but I am curious what a wet compartment would tell. Also, you say sensor quite a few times, I just want to make sure that I am following: is the accelerometer sensor the same sensor that sends a signal telling the transmission when the ABS is working? Thanks for your help thus far.


If I turn off ESP, could I test the idea that the sensor's being faulty is causing the jittering of my car up inclines?

The transmission control module is found under the passenger side carpet. Audi is notorious for water leaks. I want to make sure that is not the case with yours.If it were wet it can cause many different problems. If it's not wet don't worry about it.

The sensor under the seat,the Accelerometer works to calculate RPM and the direction the vehicle is traveling, etc. lateral or horizontal as when the car is in a spin. The sensor fails and transmits incorrect information to the transmission control module
Roman and other Audi Specialists are ready to help you
Customer: replied 3 years ago.

First, I want you to clarify what transmission issue is solved when replacing the sensor. At first I thought you were referring to the vibration issue I was having, but I now think that you were talking about the fault code issue (one being present in ABS controller, but not any codes in the transmission controller). Which were you referring to?


Regardless, back to the vibration issue: could my trouble I described in the original post be a bad CV joint or multiple bad CV joints? I notice that as I coast and slow down to a red light, for example, I feel/hear an ever-so slight ticking or popping. This occurs at decreasing speeds <20mph and on flat streets with my wheels pointed straight. Could CV joints be causing this tick/pop as well as my vibrations I feel on acceleration up an incline?

the cv joints make noise when the rubber boot has been torn open and the grease comes out and when you are turning the outer joints make noise, while going straight it would be the inner joints. You will have to inspect them.

The lateral sensor works in conjunction with the ABS and the transmission.

I believe that you may have more than one problem and will have to have the vehicle inspected.