P30FF, help please!!!

[ABHuynh]

Hi everyone, thanks in advanced for this!

I'm about to smog check my car and I just put back on a stock downpipe that I bought from one of the members here. I'm transitioning from the AR design downpipes that I've been using for a little over a year and I've been on a Cobb stage 1 tune without any problems at all.

The weird thing is that after I installed the stock downpipes, I'm now getting a P30FF code. I've searched the forums and I understand it's a boost leak but I just took it to a mechanic today and he couldn't find anything--he tried looking at the waste gate, etc. A BMW mechanic took a look at it but he couldn't find anything wrong--do you guys have any insight for what I can do? The car was running flawlessly before and was able to get good numbers with boost PSI and everything.

When I rev the car with slight pressure on the throttle, it feels really slow--like limp mode, and the check engine light comes on in the center display. It goes away right away after I turn off the car and turn it on again. I'm back on a stock tune with the accessport and tried unpairing it, but nothing has worked so far.

Please help!!

[tglazed]

Maybe check the vacuum lines running to the boost control solenoid type thing. They get split open and develops boost leaks. It is on the passenger side of the motor directly on the side of the 6 cylinders. It almost runs into the intake manifold if I remember right. But I had some there.

[Mr Gasser]

Check all the piping, there has to be a leak somewhere...hope you were a sloppy tech and forgot to tighten something...lol. If problem persist, you are going to have to program the turbos to send less boost, they may be starting to wear out, how many miles?

I think Cobb may be able to sent you a tune if you give them some log data.

[kprocivic]

good advice. also check your chargepipe for leaks/ and or diverter valves also.

[1mang]

Check all vacuum lines (especially the ones near the oil filter housing). They tend to crack over time due to heat and just general wear and tear.

Another thing might be rubber O-rings on the diverter valves hardened up over time due to heat and just general wear and tear.

I replaced all and it seemed to have fixed my issues of underboost. Here is a reference for the diverter valve o-rings

http://www.german**********/showthre...ter-Valve-Seal

[The Wind Breezes]

You probably knocked something loose or disconnected something and forgot about it.

Originally Posted by Mr Gasser

If problem persist, you are going to have to program the turbos to send less boost, they may be starting to wear out, how many miles?

Award for the most confidently given bullshit advice of the day will almost surely go to you! Please wait another 12 hours to collect your prize.

[Mr Gasser]

^^^Actually it seems more like Cobb's BS advice as shown here:
https://cobbtuning.zendesk.com/hc/en...Code-Diagnosis
I'm just the messenger, the UPS (whatever) delivery guy.