VW

Have Volkswagen Questions? Ask an Expert Now.

Ask an Expert,
Get an Answer ASAP!

I have rough engine idle on my 1999 4-cyl VW Passat. I found…

Customer Question
I have rough engine...

I have rough engine idle on my 1999 4-cyl VW Passat. I found a one foot vaccume hose, clear on one end, with a right angle 1/2" opening on the other end. I have no idea where this connects to. Check engine light is on.

Mechanic's Assistant: Does the light stay on, or does it blink?

Blinks

Mechanic's Assistant: Are you fixing your Passat yourself? What have you tried so far?

Sorry...light is constant. I have not done anything yet.

Mechanic's Assistant: Anything else you want the mechanic to know before I connect you?

No; all is well otherwise.

Submitted: 2 months ago.Category: VW
Show More
Show Less
Ask Your Own VW Question
Customer reply replied 2 months ago
The hose is about 18" L-shaped on one end, clear on the other.
Answered in 2 minutes by:
5/29/2018
VW Mechanic: David Craig, Auto Mechanic replied 2 months ago
David Craig
David Craig, Auto Mechanic
Category: VW
Satisfied Customers: 6,008
Experience: Owner/Mechanic at 3D Automotive
Verified

Hi my name is ***** ***** I'll be more than happy to assist you, Please allow me a few minutes to review your information. Thank you.

Ask Your Own VW Question
VW Mechanic: David Craig, Auto Mechanic replied 2 months ago

what fault code are you getting?

Ask Your Own VW Question
VW Mechanic: David Craig, Auto Mechanic replied 2 months ago

also please upload a pic of the hose in question

Ask Your Own VW Question
Customer reply replied 2 months ago
I'm not; I haven't hooked up a laptop. It's a rough idle with loss of power. Just a steady check engine light. I'll try sending photo of hose.
VW Mechanic: David Craig, Auto Mechanic replied 2 months ago

ok but you have to be getting a fault code. I need to know what that is

Ask Your Own VW Question
Customer reply replied 2 months ago
Where would I see th fault code?
VW Mechanic: David Craig, Auto Mechanic replied 2 months ago

you need a code reader

Ask Your Own VW Question
Customer reply replied 2 months ago
I have a new code reader. Where do I plug in?
VW Mechanic: David Craig, Auto Mechanic replied 2 months ago

under the dash at the obd 2 diagnostic port.

Ask Your Own VW Question
Customer reply replied 2 months ago
No. I'll send you a photo. Where do I send.
VW Mechanic: David Craig, Auto Mechanic replied 2 months ago

below cover next to the parking brake lever

Ask Your Own VW Question
VW Mechanic: David Craig, Auto Mechanic replied 2 months ago

you attach the photo to the paperclip icon

Ask Your Own VW Question
Customer reply replied 2 months ago
Let's forget it for now. I'll take it to me mechanic in the morning.Thanks.
VW Mechanic: David Craig, Auto Mechanic replied 2 months ago

ok

Ask Your Own VW Question
VW Mechanic: David Craig, Auto Mechanic replied 2 months ago

standby

Ask Your Own VW Question
VW Mechanic: David Craig, Auto Mechanic replied 2 months ago

Im going to open this up to the others. that does not look at all familiar

Ask Your Own VW Question
VW Mechanic: ,  replied 2 months ago
Verified
Phone call session started
Customer reply replied 2 months ago

Please cancel my subscription. Thanks, Chris *****

VW Mechanic: Danny, VW Mechanic replied 2 months ago
Danny
Danny, VW Mechanic
Category: VW
Satisfied Customers: 4,621
Experience: ASE Master Certified with L1 Certification, Volkswagen Certified, VW and Audi repair shop owner
Verified

That doesn't connect to anything, somebody ghetto rigged your system. If you want to cancel then fine, but I know exactly what's up with your vehicle, I'm a VW and Audi specialist with a youtube channel sponsored by continental and pentosin, and I can tell you EXACTLY what needs to be done to fix it....

Ask Your Own VW Question
VW Mechanic: Danny, VW Mechanic replied 2 months ago

I promise you that if you leave here, you're going to either not ever figure it out, or you're going to spend a thousand dollars at a shop to fix it right.

Ask Your Own VW Question
VW Mechanic: Danny, VW Mechanic replied 2 months ago

Oh, and I already have a link to the parts you need ready to go.

Ask Your Own VW Question
Customer reply replied 2 months ago
I was able to run the code: 0303. Cylinder #3 misfiring. I have to get to work. Hold off on the cancellation. Will try getting back to you later today.
VW Mechanic: Danny, VW Mechanic replied 2 months ago

Cylinder 3 misfire is not a cause, it's a symptom. The fault is because you have a giant vacuum leak because your breather system is missing.

https://www.ecstuning.com/b-assembled-by-ecs-parts/emissions-service-kit/06a129101dkt1kt/?gclid=Cj0KCQjw9LPYBRDSARIsAHL7J5kCR1BbwCJWM_bl6YLqczAhiT64ByolFkP51-OWvJPd9qrPhY2N6iQaAhmSEALw_wcB

Take a look at this kit, you need most of that, with the exception of the metal pipe along the top left, and the metal elbow in the middle. Basically there's a 3 way hose off the valvecover, one of those runs to that metal pipe that runs along the side of the motor to the flat pancake type breather valve you see on the right, which goes in the intake pipe near the mass airflow sensor.

Then there's an elbow off the oil filter housing that goes to that 3 way small plastic PCV valve, which then runs up to the 3 way pipe on the intake.

https://www.ecstuning.com/Volkswagen-Passat_B5-FWD-1.8T/Search/Suction/

You also need that suction jet pump, which creates brake boost using vacuum and is also a crankcase ventilation valve.

This system is likely missing from your engine, and that creates vacuum leaks. If you read your mass airflow sensor flow it should be 3.5 grams per second at idle and 10.5 at 2000 rpm while the vehicle is in park. If it reads low at idle and fine or close to fine at 2000 rpm then you have a vacuum leak, if its fine at idle but low at 2000 rpm the maf is bad.

When this system fails and falls apart it causes oil vapor to kill the mass airflow sensor as well, so it may be reading low all the time.

Additionally if you look down between the intake runners with a flashlight you'll see where the elbow attaches to the oilfilter housing, and the black sludge you see in that, will likely fall down into the oil pan when you do the repair, causing you to lose oil pressure.

Until you're prepared to remove the valvecover cam adjuster seals and oil pan, scrape them clean, replace the pump pickup, then replace the breather and reinstall the valve cover, cam adjuster seals, and oil pan, you're probably better off not messing with it. Last time I thought I'd get lucky it lost oil pressure 20 minutes later, and ended up getting impounded because it broke down in the middle of Seattle on the HWY in a no parking zone. DO NOT attempt I warn you.

If you google "1.8t sludge campaign' you'll find a lot of information about what you need to do, only it used to be done because people didn't use synthetic oil and they lost pressure so VW paid to do all of this. NOW, the sludge has clogged the breather/pcv system, you undoubtedly have severe oil leaks at the back of the cylinder head, which are leaking on the coolant flange, eating that seal and it's about to fail, has failed, or recently was replaced. There's a small tool vw3366 you need to compress the cam adjuster and pull the seals out of that. If you pull your oil cap and run your fingernail down the inside of the valvecover it's going to be coated in a black gunk that looks like you burned something in a frying pan, and that stuff is coating the oil pan, and the oil pump pickup will nearly completely blocked.

You have to drop the bolts on the front of the subframe and loosen the back ones, which means supporting the engine with an engine bar or cherry picker, so you can get the lower half of the oil pan off on this model. It's about 7 hours of work, but if you do it yourself it's a few hundred in parts, and it'll run like BRAND NEW. You'll never ever get it to run right if you don't do this, it will always have oil leaks and improper fuel trims, a rough idle, and lack power, and eventually you'll lose oil pressure. It needs to be done or probably just sell the vehicle before it turns into a nightmare of even more epic proportion.

I do performance tunes for a living, I have a tune that makes like 300 hp on this vehicle, so I'm pretty familiar with it and how to fix it, I'm in the process of making a video for this concern right now for my youtube and website. I had to mess with it on my sisters car last week in fact.

Let me know if you need more info or have more questions. And I'm just a contractor I don't get paid until you hit accept.

Ask Your Own VW Question
Customer reply replied 2 months ago

Danny...I took the car to my mechanic, and yes, it was the #3 cylinder ignition coil; while there they will also replace the plugs and wires. Cost" $400. While I could have done this myself, I simply don't have the time. Anyway, thanks for your offer to help. Please cancel my subscription. Chris *****

VW Mechanic: Danny, VW Mechanic replied 2 months ago

This is NOT repaired, I'm putting you in for a refund. I suggest you find yourself a local VW specialty shop. I don't care that I'm not getting paid, which I didn't because you didn't accept. I'm TRYING to warn you. Go spin by a local VW specialist and just pop your hood for them and see what they say. I can tell where you took it is a generic shop by what you just told me.

I hope they didn't charge you for spark plug wires, because your vehicle doesn't even have plug wires.

Ask Your Own VW Question
Was this answer helpful?

How JustAnswer works

step-image
Describe your issueThe assistant will guide you
step-image
Chat 1:1 with a vw mechanicLicensed Experts are available 24/7
step-image
100% satisfaction guaranteeGet all the answers you need
Ask Danny Your Own Question
Danny
Danny
Danny, VW Mechanic
Category: VW
Satisfied Customers: 4,621
4,621 Satisfied Customers
Experience: ASE Master Certified with L1 Certification, Volkswagen Certified, VW and Audi repair shop owner

Danny is online now

A new question is answered every 9 seconds

How JustAnswer works:

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

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 PElm 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.

PhilMarysville, 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.

CharlesWalnut 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!

SueCharleston, 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.

JimCastleberry, 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

< Previous | Next >

Meet the Experts:

vwnewton

vwnewton

VW Owner,ASE Master and L1 Advanced

307 satisfied customers

25 years of VW obsession turned into a job, last 15 years as a VW Tech.

VWDoc

VWDoc

Independent VW Shop owner

1,764 satisfied customers

20 years of experience working with VW's. Independent European shop owner and technician.

Martin

Martin

auto electrical

804 satisfied customers

South African Trade Diploma in Auto Electrical

Matt

Matt

Engineer

708 satisfied customers

Mechanical Engineer with 20 years experience in the auto industry, 8 yrs in formula 1 engine testing

Tim&#039;s Auto Repair

Tim's Auto Repair

mechanic

484 satisfied customers

Have owned a repair shop for 25 yrs.

Tim Mohr

Tim Mohr

ASE MASTER TECH

419 satisfied customers

30 YRS EXPERIENCE, FOREIGN AND DOMESTIC, GAS AND DEISEL

Chris(aka-Moose)

Chris(aka-Moose)

VW Technician

286 satisfied customers

16 years of experience

< Previous | Next >

Related VW Questions
Where can I get fittings to go on the hoses to read high and
Where can I get fittings to go on the hoses to read high and low pressure. My standard a/c manifold will not connect … read more
kyle swart
kyle swart
Certificate Of Completion, Automotive Technology
330 satisfied customers
Check engine light flashing idle rough all on start up.
Check engine light flashing idle rough all on start up. … read more
Gunvir Singh
Gunvir Singh
1,949 satisfied customers
Yesterday my wife drove about a mile from home when suddenly
Yesterday my wife drove about a mile from home when suddenly the check engine light came on and the car started to run like it was on 2 cylinders. When I got there the EPC light was also on and yes it… read more
internal88
internal88
Product Manger
Bachelor's Degree
623 satisfied customers
Engine code 17519, yes, mechanics cleared more then 10 codes
yes, mechanics cleared more then 10 codes but that one remains … read more
Wolfgang
Wolfgang
11 satisfied customers
Volkswagen Passat GLX: 97 vw Passat; 1st fan runs long time
97 vw Passat; 1st fan runs long time after engine turned off/ multi tries before engine catches; then I noticed brake /airbags warning lights come on & stay on MOST of the time; I had to jump car seve… read more
gomi_otaku
gomi_otaku
Auto Technician (dealership)
Vocational, Technical or Trade Scho
2,229 satisfied customers
Volkswagen Passat: I have a 2004 VW Passat 1.8t auto/tiptronic
I have a 2004 VW Passat 1.8t auto/tiptronic that has the following codes: 16825 - EVAP Emission Control Sys Incorrect Flow P0441 Lower Limit Reached, 16514 - O2 Sensor Bank 1 Sensor 1 Malfunction in C… read more
vwtech0405
vwtech0405
VW Technician
Associate Degree
8,868 satisfied customers
Volkswagen vw passat: 2001 VW Passat misfire for like 10mins
2001 VW Passat misfire for like 10mins then runs ok. Sometimes brake padel is hard too but that also works after a while. Codes are p0300,p0302,p0303. Replaced mass air sensor, switched coils, replace… read more
Wolfgang
Wolfgang
11 satisfied customers
Volkswagen Passat I have a 2003 VW Passat 1.8T. OBD11 codes
I have a 2003 VW Passat 1.8T. OBD11 codes P0300, P0301,P0302, AND p0171 are coming on. I have changed the plugs, coill pack, rewire connectors, replkaced maf, and replaced a connector vacuum hose. The… read more
gomi_otaku
gomi_otaku
Auto Technician (dealership)
Vocational, Technical or Trade Scho
2,229 satisfied customers
I have a cel that blinks when i first start the car..sputters..turbo
I have a cel that blinks when i first start the car then goes solid. It has a loss in power, sputters when first accellerating and doesnt seem to have any turbo. My mechanic thought I might have got s… read more
gomi_otaku
gomi_otaku
Auto Technician (dealership)
Vocational, Technical or Trade Scho
2,229 satisfied customers
2003 VW Passat: Fan blows..Car and engine compartment..rust
I just purchased a 2003 VW Passat Wagon 4motion for my daughter and the heater does not work. Fan blows, but no heat. Car and engine compartment in excellent shape and no rust. Is there a simple fix, … read more
Danny
Danny
VW Mechanic
High School or GED
4,621 satisfied customers
2002 VW Passat: it started running..dashboard..car idles very rough
I have a 2002 VW Passat last night it started running rougn and I am getting a blinking light on the dashboard, the engine icon is blinking, car idles very rough and doesn't have much power… read more
Danny
Danny
VW Mechanic
High School or GED
4,621 satisfied customers
VW jetta: speed manual transmission..I have a check engine light..lean
I have A1996 VW jetta, 4 door sedan, 2.0 litter engine, 5 speed manual transmission. I have a check engine light, with a code p-0171 to lean the vw code is p 1128 to lean.I also have a rough idle When… read more
Danny
Danny
VW Mechanic
High School or GED
4,621 satisfied customers
2003 VW Passat: 000 miles..changing..belts, spark plugs etc
I have a 2003 VW Passat. The car has 126,000 miles. Have done all the maintenance including changing belts, spark plugs etc. Recently, the engine maintenance light has gone on...yellow...and stayed on… read more
gomi_otaku
gomi_otaku
Auto Technician (dealership)
Vocational, Technical or Trade Scho
2,229 satisfied customers
Passat: 03..the car shakes when shifting speeds..accelerate
Car: Passat '03 1.8 Turbo. During acceleration the car shakes when shifting speeds. If acceleration is to big, engine fault blinks and it does not accelerate. ignition coils have been replaced twice e… read more
gomi_otaku
gomi_otaku
Auto Technician (dealership)
Vocational, Technical or Trade Scho
2,229 satisfied customers
2003 volkswagen passat: dealership..check engine light (code P0171)
I have a 2003 volkswagen passat 1.8T . I just bought this vehicle 1 month ago from a dealership. Now a week ago, I got check engine light (code P0171), and the light stayed there not blinking. light w… read more
gomi_otaku
gomi_otaku
Auto Technician (dealership)
Vocational, Technical or Trade Scho
2,229 satisfied customers
Wagon: Passat..idling..a junction the engine surges as if it..engage
We have a 1999 1.8 Passat station wagon. Sometimes when idling at a junction the engine surges as if it is trying to engage the automatic gearbox. Would it be the thottle butterfly and how easy is it … read more
vwnewton
vwnewton
VW Owner,ASE Master and L1 Advanced
A.S.E. L1 Master and more
307 satisfied customers
I have a 2004 Passat. There is vibration when you are stopped
I have a 2004 Passat. There is vibration when you are stopped and in gear. There is also vibration when you accelerate. An independent shop changed the front two engine mounts and the center mount. It… read more
gomi_otaku
gomi_otaku
Auto Technician (dealership)
Vocational, Technical or Trade Scho
2,229 satisfied customers
2003 VW Passat: running rough..park..the air filter..runs better
I have a 2003 VW Passat that was running rough when in park. I changed the air filter and it runs better, but now the picture of the engine is showing. What does that mean?… read more
Ryan Suliman
Ryan Suliman
High School or GED
40 satisfied customers
Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Show MoreShow Less

Ask Your Question

x