[CoastE90]

I have a 2011 N55 335i, 4/10 build date, 16k miles (long story). I am getting the SES light / half engine indicator, reduced engine power etc. message. My BT reads out 2C71 Charge air pressure sensor: pressure too high. The car has no unusual symptoms; it drives fine although I haven't tried any WOT.

No obvious physical indicators or weird noises under the hood.

I cleared the code...start the car up once, its fine...start the car a second time the SES light / half engine indicator and the 2C71 code returns.

Any ideas what may be causing charge air pressure to be too high? Bad wastegate?

Thanks for any thoughts...

[Jsoboti]

Originally Posted by CoastE90

I have a 2011 N55 335i, 4/10 build date, 16k miles (long story). I am getting the SES light / half engine indicator, reduced engine power etc. message. My BT reads out 2C71 Charge air pressure sensor: pressure too high. The car has no unusual symptoms; it drives fine although I haven't tried any WOT.

No obvious physical indicators or weird noises under the hood.

I cleared the code...start the car up once, its fine...start the car a second time the SES light / half engine indicator and the 2C71 code returns.

Any ideas what may be causing charge air pressure to be too high? Bad wastegate?

Thanks for any thoughts...

Mods?

[CoastE90]

No mods. Completely stock.

[rhm135]

Returns immediately on second crank without driving?

[CoastE90]

Originally Posted by rhm135

Returns immediately on second crank without driving?

Correct.

[rhm135]

Sounds like a wiring or sensor issue if it sets that quickly. Have you inspected the boost sensor/wiring before the
throttle body?

[CoastE90]

Originally Posted by rhm135

Sounds like a wiring or sensor issue if it sets that quickly. Have you inspected the boost sensor/wiring before the
throttle body?

I really hope you're right...I ended up bringing the car into the dealer to get looked at. After I described the problem they had the same thought you did. I'm still waiting to hear from them what they found once they started work. It's going to be a while as we're all about to be buried under two feet of snow.

Thanks for taking the time to post.

[rhm135]

Originally Posted by CoastE90

I really hope you're right...I ended up bringing the car into the dealer to get looked at. After I described the problem they had the same thought you did. I'm still waiting to hear from them what they found once they started work. It's going to be a while as we're all about to be buried under two feet of snow.

Thanks for taking the time to post.

No problem. Keep me posted on what they find.

[CoastE90]

Following up here...it took the dealer three weeks to figure it out (!!), but the problem was caused by a faulty intake air pressure sensor. rhm135 you were right on the money . Dealer replaced the sensor (part # 13-62-7-585-493).

[rhm135]

Nice! Good to hear you got it fixed.