Hey Guys,

Seems like after 110K miles everything breaks on my B7. I've kept is running flawlessly for 55K and now everything is popping up.

Well this time around I have a couple of new CEL codes that I want to get straightened out but with the weather and snow storms I haven't had a whole lot of time to peak under the hood for extended periods of time.

I have 3 codes right now: P2181 (Cooling System Performance), P0507 (Idle Control System RPM Higher Than Expected) and P12A2 (No Information).

I've had P2181 for a while, and I'm guessing its my thermostat. Temperature gauge only gets a little above the 1/4 mark when it used to sit up at the 1/2 mark. Not too worried about that one.

P0507 came up about 2 weeks ago on the coldest day. I noticed at a stop light that my idle was creeping up to about 1800 then going back down to 900. It would repeat this cycle but at the low end it would seem to idle pretty rough (noticeable vibration). From reading forum posts I'm guessing something to do with the vacuum system. Haven't had a change to really look at it but I did pull the dipstick out while the engine was running (as someone had mentioned to do) and there was a lot suction coming from it. Could this be a bad PCV? I didn't notice anything wrong with the hoses around the PCV but if anyone has any ideas on where to look for an issue that would be most helpful!

Now P12A2 I haven't found anything on yet... but it came up in conjunction with P0507 so I'm guessing its related.

While we're on the topic of PCV, I was considering the BSH PCV revamp ( BSH 2.0T FSI PCV Revamp - BSH Speedshop ) but I guess I don't really know what I am accomplishing by doing it... if I'm accomplishing anything at all lol. Just to eliminate the PCV by converting to vacuum only to eliminate the PCV from failing like it may have? I guess that makes sense... Correct me if I'm wrong!

Any thoughts would be much appreciated.

-Jago

 

Hey Jago,

P2181 is definitely thermostat.

P0507 and 12A2 are related and it is indeed vacuum. When this happened to me, the cap on my intake manifold popped off on a really cold day (like single digits). My guess was that it was because I removed a tap that was feeding a forge diverter valve when I went back to the latest OEM revision DV. The cap was probably weakened from being removed and reinstalled, so I threw a new one on with a hose clamp and havent had a problem. Anyway, if it's not that then it's somewhere around PCV I'd guess.

FWIW I have the BSH PCV revamp. No noticeable improvement in anything, but it looks nice and feels more "solid" than the OEM PCV.

Good luck.

 

Hey Damaniac311 thanks for the response!

Sounds almost exactly the same as my situation. I'll have to take a look again and see if I can find the cap. Doesn't seem to be coming to mind where it is. I'll go through it with a fine tooth comb and hopefully solve it.

Thanks again!

-Jago

 

It's located on the back of the manifold, lower and to the left of where the PCV line connects to the manifold. Mine looked like a big rubber bullet.

 

Finally got it up here to my Dad's shop to work on it. Popped the hood and listened to it for a bit, then turned it off and listened... Heard a loud hissing for about 15 seconds after I turned it off... Definitely a leak somewhere near the PCV... Drives me mad that I can't pinpoint its exact location!

Anyway, got a new PCV and gasket, maybe that is all it needs...

Also doing thermostat. Might try to make a video of this...

Story at 11.

-Jago

 

PCV install was a success! Those hoses are stupid hard to get off. Must have some magic tool to get that bottom one off without snapping the plastic clips... I only did on one side... but it seems to be a pretty good fit still on the new PCV.

Took it for a test drive and its purring like a kitten now.

I took a video of the install... maybe put that together to help others and point out how easy it is to break those clips!

Thermostat can wait for another day... I'll quit while I'm ahead tonight.

-Jago