'01 VW Jetta 1.8T Misfire

[sinSStr]

P0172 - Fuel system too rich bank 1
P0300 - Random misfire
P0301-304 - All cylinders misfiring

Thoughts? I haven't gotten a chance to look at it yet...just wanna get an idea on where to start.

[Slow35th]

Johns will give you 200 bucks. Maybe.

[sinSStr]

So far I'm reading about vacuum leaks, o2 sensors, and coils being common issues.

The hoses that are prone to leak/crack are the ones under the intake near
number 3 & 4 cylinders. Usually a sign of leakage is if the hoses have some
oily build up.

[Slow35th]

Johns will give you 200 bucks. Maybe.

Bump

[Turbohwagon]

Check for vacuum leaks first, i've found a few intercoolers with cracked/broken tanks.

[Turbohwagon]

The MAF sensors on these turds take a dump quite frequently.

[sinSStr]

The MAF sensors on these turds take a dump quite frequently.

There a way to test it w/o a scanner?

[Turbohwagon]

There a way to test it w/o a scanner?

With out a scanner? I usually check g/s of air in the datastream. Replace with known good MAF i guess. You might not be able to return it unless you're giving out handies to the guys at pepbrahs.

[sinSStr]

Well I guess step one will be to search for a vacuum leak. I'll do that.

[95 whitestang]

Wouldnt a vac. leak cause a lean code not a rich one? Maybe your oxygen sensor is fucked or possibly the fuel pressure regulator ruptured? Either way I really dislike these fucking cars.

[sinSStr]

Wouldnt a vac. leak cause a lean code not a rich one? Maybe your oxygen sensor is fucked or possibly the fuel pressure regulator ruptured? Either way I really dislike these fucking cars.

That was my thought. Germans do things weird though. One of the first posts I came across mentioned a bad upstream o2...

[Notch]

Either way I really dislike these fucking cars.

.T

[95 whitestang]

That was my thought. Germans do things weird though. One of the first posts I came across mentioned a bad upstream o2...

That would be my thought. I just had bad O2's give me a headache on a 93 LT1 camaro that was running pig rich all the time.

[Turbohwagon]

Wouldnt a vac. leak cause a lean code not a rich one? Maybe your oxygen sensor is fucked or possibly the fuel pressure regulator ruptured? Either way I really dislike these fucking cars.

Under boost it would show as a rich condition, you would be pulling more air through the MAF, but the extra air would be escaping through the leak instead of entering the cylinder. It takes NOTHING to spool the turbo on these hunks of dog shit, smallest turbine housing ever.

A bad upstream O2 could be it. You might be able to isolate it by unplugging it and see what it does, the computer should go Open loop mode once the O2 signal is lost.

A scan tool would be ideal.

[95 whitestang]

Under boost it would show as a rich condition, you would be pulling more air through the MAF, but the extra air would be escaping through the leak instead of entering the cylinder. It takes NOTHING to spool the turbo on these hunks of dog shit, smallest turbine housing ever.

A bad upstream O2 could be it. You might be able to isolate it by unplugging it and see what it does, the computer should go Open loop mode once the O2 signal is lost.

A scan tool would be ideal.

Thanks for the correction. I so rarely work on factory boosted cars, that this never crossed my mind. It makes perfect sense. But I still think VAG cars are pure junk.