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akamrchubs
07-19-2016, 11:48 AM
Hello! First post, long time lurker.
I have a 2001 audi a4 1.8t manual FWD. recently i have had my car sputter/misfire/hesitate while accelerating hard. Ive done the usual spark plug, MAF, scanned the car for codes. It gives me a p0172 which means its running rich. I started hearing air coming out from my drivers side , up untill recently i only heard the turbo spool up on the passenger side. But this happens intermittently. Sometimes i hear it sometimes i dont.
If anyone can point me in the right direction to fix this issue it would be much appreciated. Thanks

MarcRogers
07-19-2016, 11:54 AM
Do the ICM(junk) delete/coil pack upgrade. You've done all of the other things. That's your last shot. IMO. And to why your running rich? Any mods?


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akamrchubs
07-19-2016, 12:03 PM
exhaust. and 2 1/2 in piping. I read that the code could be thrown because of a unseated dipstick. my dipstick tube broke off so ive plugged it with some rubber grommets ive found. but i couldnt see that would lead to my engine misfiring.
what is a coil pack delete? please explain more.

MetalMan
07-19-2016, 12:11 PM
Do the ICM(junk) delete/coil pack upgrade. You've done all of the other things. That's your last shot. IMO. And to why your running rich? Any mods?

His car doesn't have the ICM.

Perform a boost leak test. Chances are good you have a torn hose somewhere.

MarcRogers
07-19-2016, 12:22 PM
exhaust. and 2 1/2 in piping. I read that the code could be thrown because of a unseated dipstick. my dipstick tube broke off so ive plugged it with some rubber grommets ive found. but i couldnt see that would lead to my engine misfiring.
what is a coil pack delete? please explain more.

Coil conversion it's an AEB thing. It defeats the ICM and upgrades the coil packs to anything not AEB. It lets you run a larger more efficient gap on the spark plug. But this is nothing to you because you don't have an ICM.


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akamrchubs
07-19-2016, 12:26 PM
is there any method to check a boost leak without a compressor?

MarcRogers
07-19-2016, 12:28 PM
Yes I don't know if the top of my head but I know there's a couple DIYs on here that will help


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MarcRogers
07-19-2016, 12:29 PM
Actually. YouTube will be a better help. Lol


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GOODBYNAAIR
07-19-2016, 12:50 PM
exhaust. and 2 1/2 in piping. I read that the code could be thrown because of a unseated dipstick. my dipstick tube broke off so ive plugged it with some rubber grommets ive found. but i couldnt see that would lead to my engine misfiring.
what is a coil pack delete? please explain more.

Be sure when you replace that dipstick you get a short throw dipstick.

(MvT)

akamrchubs
07-19-2016, 09:40 PM
Be sure when you replace that dipstick you get a short throw dipstick.

(MvT)

short throw? do you mean a locking dipstick?

GOODBYNAAIR
07-20-2016, 08:13 AM
short throw? do you mean a locking dipstick?

Not locking short throw.. Google = your friend.

(MvT)[:D]

Wrath And Tears
07-20-2016, 10:51 AM
Step one: scan car for codes
Step two: change coil pack of misfiring cylinder with another one far away
Step three: drive car
Step four: see if misfires follow coil
Step five: replace bad coil

Do this first (assuming the misfire is only one cylinder, if its multiple a boost leak is way more likely) and then the boost leak test. There are only three parts on the driver side that could leak. Hose from piping to the IC, the IC itself, and the TB hose.

MetalMan
07-20-2016, 11:09 AM
There are only three parts on the driver side that could leak. Hose from piping to the IC, the IC itself, and the TB hose.

The AWM has quite a few vacuum lines and things, all of which have hoses that attach to the intake manifold. If any of those hoses are torn, or check valve(s) damaged, suction jet pump damaged, PCV valve damaged, etc. then there could definitely be an air leak that may be audible (on the driver's side).

Your suggestion to check codes for single-cylinder vs. multiple-cylinder misfire is a good idea for sure, could be that the misfires and air noise aren't necessarily related.

Wrath And Tears
07-20-2016, 04:10 PM
I always forget about vacuum lines on the intake manifold. Air woosh could also be from the CCV system possibly, there's a lot of stuff on the drivers side for that.

M551_Sheridan
07-20-2016, 04:32 PM
Normal things I swap if I get a misfire: plugs, coil packs, ICM, MAF sensor, and check for vacuum leaks. Also check your diverter valve.


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akamrchubs
07-21-2016, 11:20 PM
so i yanked out the coil pack and stuck a plug in it to see if i had spark in all 4 cylinders. They do.
After changing the coilpacks around, how do i determine if the misfire is happening in a different cylinder than before?

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anyone know a good/cheap mechanic in the san fransico/ bayarea? i feel like this is gonna be way over my head.

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or can i just replace all 3 hose components and pray that will fix my problem