P30FF

[Steve1155]

Uninstalled the COBB and till have limp mode. Took it to dealer and dealer says when they scanned it it says something about the catalytic converters. I'm running catless DP's so how can that be? I checked vacuum lines before heading to the dealer. He did say one of the O2 sensors was resting on the heat shield. Think he's just using the catless as an excuse not to find the problem, what say you???

[Lmaiuri]

Why don't you read the code with COBB installed?

[Top Gon]

isn't P30FF a boost leak?

Check to make sure the wastegate actuators aren't touching the band clamps on the downpipes.

[Zombie1]

Originally Posted by Basheezy

isn't P30FF a boost leak?

Check to make sure the wastegate actuators aren't touching the band clamps on the downpipes.

Check that and the back side of your charge pipe for cracks if you can't see anything up front

[Steve1155]

My fault, let me clarify. I was driving the other day and decided to get a bit "spirited" with the accelerator. After a while I would try and get on it and the engine would rev but the car wouldnt pull. almost thought i was in neutral for a second. Sure enough limp mode went into effect. I plugged in my Cobb AP and it gave P30ff boost leak code. I went home, uninstalled the AP and headed to the dealer. Dealer said they got a catalytic converter code. Im running and have been running catless for over a year, so I dont see how that would suddenly cause the car to go into limp mode. regardless they aint gonna do anything unless i put my factory DP's back on. Any ideas of what caused it. Didnt happen until i pushed the car a bit.

[Steve1155]

Checked all the lines for a leak and didnt see or feel anything. On a side note, some have mentioned the wastegates. When i'm idling, if I rev the car i obviously hear the exhaust get louder but upon releasing the accelerator the exhaust noise lowers as normal but right at the end before its about to get to idling RPM's, i hear a slight shutter/metalic rattle noise. Could this P30ff issue be the wastegates.

[ErvGotti]

P30FF can be a boost leak, a broken boost solenoid or it's corresponding lines, or waste gate issue. The reason the dealer is pulling a Catalytic code is beacuse you are running catless DP's without a tune to suppress the code. Without the tune to suppress the DP code your car thinks that the cats are bad hence the code. Most dealerships will not work with cars with catless DP's.

[Steve1155]

Makes sense Erv, but in the past when I've had any issues and had to go to the dealership, I've removed the tune, taken it in for whatever the problem was, and re installed the tune when I got home without a code popping up for the lack cats.
Come to think of it I had the limp mode half engine symbol appear. I then cleared it and removed the tune. On the drive to the dealer the limp mode did not engage BUT the check engine light came on. This is what they read which stated boost catalyst 2 blah blah blah. They stopped right there. Now I got the car back and cleared everything. No lights on but I can tell it isn't boosting all the way. Suggestions anyone? I can go back to the dealer with no lights or faults on and just tell them it's not boosting.

[fboutlaw]

P30FF is boost leak. I've dealt with this shitty code for 2.5 years. It only would pop up for me on the track under heavy acceleration and go away after.

There's a good thread on e90 forums, but... this issue means there is boost leaking.

I went through this process because of the "it could be anything" fear
1. Replace diverter valves with BOV - did not fix
2. Remove exhaust and tighten wastegate pushrods - did not fix
3. Finally decide to check the rest of the air system and removed the intercooler. No issue with intercooler... BUT I was missing the pre-formed seal (nitrile x shaped o-ring) between the intercooler and pipes from the turbos. Replaced that and no more issue. Tested at Laguna last Monday. Pounded on the car, no issue.

Likely you really do have boost leak. Something in your system is leaking air.

I recommend the following, stop when fixed:
1. Check the components you can see, all the small vacuum lines and make sure everything is plugged in.
2. Pull off the splash shield and check your intercooler for damage and make sure there's a green o-ring at the inlet and a black one at the outlet.
3. Pull off your charge pipe and diverter valves and look for anything broken. Note that there is one clamp ring you have to break and will need a new one to replace it at the side of your charge pipe that goes to your intercooler.
4. Adjust wastegates. You can get to the back one without taking any components off with a 4mm and 10mm midget wrench. You have to make sure the engine is totally cold, remove passenger front wheel, crawl under car side to side and shove your left arm up to the diverter valves following the downpipes. Tighten the rod until slack is taken up... Now the front one... it'd be hard to get to without removing the entire front sub-frame. Good luck.
5. If none of the above work, remove your tune, make sure the code is active and take it to a bmw dealer.

Good luck and PM if any questions.

Likely it's something totally stupid and never installed by BMW or a seal damaged during a mod / garage visit and a simple cheap fix.