problem with 7A

[John.]

Just a thought I had wandering idle problems for a number of years on my 90 quattro with 7a engine, having gone thru the usual suspects (stable valve, maf, relays etc.) I finally sorted it by replacing the temp sensor on the rear of the cylinder head.

Interesting to know.

[quattrodave]

Just a thought I had wandering idle problems for a number of years on my 90 quattro with 7a engine, having gone thru the usual suspects (stable valve, maf, relays etc.) I finally sorted it by replacing the temp sensor on the rear of the cylinder head.

[PeterS]

first - the crankcase vent from the left side of the engine (from the passenger compartment view) connects via the pipe to the intake hose between the Mass airflow (MAF) sensor and the throttle body. it is designed to allow crankcase fumes to be re-entered into the engine for combustion. You could vent that to atmosphere for now with no running issues but higher emissions, The bigger issue is that If there are vacuum leaks between the MAF and the throttle body that is considered "unmeasured" air and it will cause running issues. Often the rubber boot between the MAF and TB gets torn underneath where that crankcase pipe enters it. Also, in other cases, the pipe becomes clogged and causes issues with proper crankcase breathing. Solution for that is to remove it from the vehicle and either use solvents to break down the blockage, or easier to light it on fire and allow it to burn off the crud.

[Mikemul]

https://www.ebay.co.uk/itm/054103211...QAAOSw63Re6tjX

I have order one. But now the other problems?

[Mikes2]

Audi Tradition have that breather pipe

[John.]

Thanks, but i mean number 2 in the picture. Is this a pipe? Where can i order it.

https://www.ebay.co.uk/itm/054103211...QAAOSw63Re6tjX

[Mikemul]

In your 3rd picture (showing end of head and distributer), I'm assuming that pipe is no. 1 in this parts diagram?

https://7zap.com/en/catalog/cars/Aud...103860::103086

Thanks, but i mean number 2 in the picture. Is this a pipe? Where can i order it.

[Lago Blue]

Hi Sir,

Perhaps (if I can't post or link a drawing below) you can copy and mark on the intake drawing at the "page 9" link above what is missing, and post it. We need a shared vocabulary for components. Perhaps gas-valve is the the throttle-body with two butterflies inside, that the throttle-cable attaches to? Is Carter-breathing possibly the crank-case breather from the block down at its' lower left side, to the big bent Michelin-man-like intake hose between MAF and throttle-body? Try to sample the fluid inside the manifold.

[John.]

…. is there anyone who have a picture of the pipe?

In your 3rd picture (showing end of head and distributer), I'm assuming that pipe is no. 1 in this parts diagram?

https://7zap.com/en/catalog/cars/Aud...103860::103086

[Mikemul]

Hi Sir,

To start with, have a read through "wandering Idle" here:

http://20v.org/engprob.htm

I have read the Text. I have check the idle motor. I removed the connector but there is no hearable differents. I think the car is in the choke modes and gives too much fuel. I will change all the vacuüm hoses but i think it will not give a change at it. One connector is broken from the Cooling temperature but it is the sensor that is for the fan.

I hope you can help me with it.

[Mikemul]

Currently, I can't upload any images, so instead, please say the model year of your car and can you post a photo of the (missing?) pipe?

Alternatively, go to page 9 here, does it show your the pipe in question?

https://www.onlymanuals.com/audi/qua...rvice_training

The build year of the car is 1989 and I dont have the pipe. It comes from the carterbreathing pipe and go into the intake tube before the gasvalve

[Lago Blue]

Currently, I can't upload any images, so instead, please say the model year of your car and can you post a photo of the (missing?) pipe?

Alternatively, go to page 9 here, does it show your the pipe in question?

https://www.onlymanuals.com/audi/qua...rvice_training

[Lago Blue]

Hi Sir,

To start with, have a read through "wandering Idle" here:

http://20v.org/engprob.htm

[Mikemul]

hello, i have some problems with my 7A, the engine have a bad idle and fluctuating. there is no pipe on the carter breathing is this a problem? the hole in the intake tube is sealed up so there is no leaking. is there anyone who have a picture of the pipe? i have remove the maf sensor to check if this was clean. is this clean enough? when i remove the maf sensor and the intake tube i was look in the gasvalve and inside the intake there is a lot of fluid. i dont know what it is. can someone help me with the bad idle problem and the other problems? i have already check the labda sensor. the engine get to much fuel at idle and the sparkplugs are black.

i hope someone can help me with one of the problems

greetings

Mike Mul