Replaced spark plugs, clean MAF. Will boost to 10 pounds but not the normal 18 pounds. Once it reaches ten pounds it will miss in cylinder 3. I also got OBD codes for Gas temp too hot. Along with a running rich code. Any ideas? I was suggested to change my fuel filter, but I really don't see that being the problem.

Thanks for the help
stu

 

An exhaust gas temp fault code will put the engine managment into limp mode which is why your not getting any boost.
You may have a faulty coil pack on cylinder which is causing the exhaust to heat up like crazy, and if you have a cat still on the car its probably close to its death.

 

did u gap the plugs right and everything? thats all i can think of.

 

A dead miss will caused raised EGTs and raw fuel to the cat, which will set those codes and prevent boost (as stated) to protect the engine and cat.

 

But call me crazy limp mode only runs 4 pounds of boost. I can hit 18 pounds of boost, but the motor is misfiring while the turbo is still spooling. Is there any way to test a coil pack? I know with the ICM you can take a volt reader to the grounds and read if it is sending enough to each side. Can you do that with a coil pack?

Thank you for your help.

 

Oh yeah i forgot you have the an ICM, that more than likely what the problem is. You can test a coil pack but those coils never go bad. I just had a brain fart.

 

Not the ICM.. Checked that already. And when the ICM goes out its cylinder 2. On top of that if it was an ICM problem it would be misfiring from the get go. Not only above 10 pounds. Any other ideas?

Thanks again.
stu

 

Uh, is that a joke? You sound more like a service advisor than a tech!

Bustin yer *****, man. I wouldn't rule out a coil pack.


Regardless if it's in limp mode, you still have a dead miss at cyl 3. A dead miss will raise EGTs and kill boost because it's missing a pulse to the turbine. Check the basics on cyl 3 (compression, spark, fuel). A clogged fuel filter would more likely cause random misfires on all cylinders. Try swapping the coil pack. If that doesn't work, pin out the connector. A spark tester between the coil pack and plug is ideal for an easy test.

 

Actually ICM's DO miss-fire on other cylinders than 2, 2 is just more common. I actually had the same problem on my friends A4, it kinda popped and missed under heavy boost, guess what......it was the ICM. Of course you should always swap the #3 coil to a different cylinder and see if the miss moves, if it doesn't..........then replace the ICM.


[blockquote]quote:

ORIGINAL: auditech79
\ You can test a coil pack but those coils never go bad.
[/blockquote]


Uh, is that a joke? You sound more like a service advisor than a tech!

Bustin yer *****, man. I wouldn't rule out a coil pack.


Funny, i did sound like a service writer right then huh.

 

^ haha, yeah, the manager and advisor at my old job were obsessed with: "Ah, that never goes bad!" It didn't matter what it was, "it" never went bad. But it drove me crazy!