Lately my car has started running very rough intermittently. It will go into reduced boost and buck very hard with any light throttle. The CEL will come on after a while and once it does the car runs fine. Eventually, a day or two later, the CEL goes out, and within a week the cycle starts over... running rough and reduced boost intermittently, followed by CEL, etc..

As listed below, my car is a 2008 SS/TC. I have the trifecta tune over GMS1 tune and sensors, Dejon SRI, and a catless DP from TurboXS.

I scanned the CEL and got the following:

P0011- Intake crankshaft position- Timing over advanced or system performance bank 1
P0010- Intake crankshaft position actuator circuit/open bank 1
P0101- MAF sensor performance
P0236- Turbocharger boost system
P2261- Turbocharger bypass valve- mechanical.

Any thoughts??

Thanks

 

What has Vince said about all this?

I'm guessing it's sensor related and perhaps you should go Forge BPV

 

p0010 is a mechanical issue.

you have to change it.

 

P0010 @ P0011> Repl. camshaft actuator solenoids for fix?!

P0101> https://www.cobaltss.net/forums/2-0l...solved-149842/

P0236> https://www.cobaltss.net/forums/2-0l...roblem-220112/

P2261> https://www.cobaltss.net/forums/2-0l...-p2261-257437/

I kind of hope these steer you in the right direction.

 

Good call on these.

 

Why? Unless he's wanting logs read or Vince recently changed the tune, there's no reason. Sounds like a mechanical issue.

 

I'm not insulting Trifecta, no need to question my inquiry. I was just thinking that Vince can see some stuff in a log that might help him pinpoint the problem. Like his MAF readings are odd. Indicating a MAF issue or Not enough boost when it's fine or it's overboosting or something.

Or

His timing is all over the place etc.

I'm just throwing out ideas to help. If they don't well I tried.

 

Thanks for those links. I emailed Vince and he agreed on the mechanical issue. I'm going to have to look into it further. Thanks for the links, Ill check those out.

In the mean time I swapped my stock intake back on and tuned down to the GMS1 tune.

 

Check your connections on your MAP sensors man. Make sure they are soldered or connected solidly with splice connectors or a crimped connection.

P0236 - Turbo Charger Boost System - Is a precursor to MAP sensor poor performance and failure either cause of a dirty maf or a bad connection. Could be a boost leak too.

 

In the past, if my car ever bucked then it was because it was going into a backup airflow calculation mode because it started ignoring either the MAP sensor or wideband O2 sensor. For those with the RPD, it will be followed by the "No Data Available" message for the Boost reading for a MAP sensor issue, message on the AFR page for an O2 sensor issue, or message on the cam phasing page for cam-related issues. It may also completely disable the cam phasing if it's a timing issue.

As mentioned earlier, it's possible that other things may have popped up at the same time or are causing the issue to be worse.

 

Ended up being the intake cam position sensor......again. They replaced it under warranty. I'm back on my Trifecta tune but Im leaving my stock intake on.

 

glad you got it fixed though. good to know for the future