2008 MS3 running rich -25 Stft at idle

[Trevor M]

I changed my turbo for another stock K04 about a month ago and everything went great, and had no codes for the first 500 miles. Now I have code p2188 and p2178 and my STFT is at -25 at idle and I'm getting terrible fuel economy. I originally had an issue with the car giving out at 4k rpms and would lug changing gears but I have since changed the MAF and it has fixed that issue but now I cannot get this code to go away. I have done a smoke test and there are no major leaks, changed the purge valve, checked both o2 sensors, and checked the bypass valve and hose. I am at a complete loss here.

 

[Awafrican]

Hello any welcome to mso.

" No major leaks" I take this to mean you see leaks" fix those they're culmative.

Mileage? Mods? Any recent work before this started? What bpv

 

[Trevor M]

140k miles and the only engine work done in the last 20k miles has been the Turbo and intercooler being replaced, I meant to say there are "no leaks" not no "major leaks". And I'm talking about the bypass/blow-off valve. The car has a cork sport cold air intake, and catback exhaust. This all started after the turbo was replaced

 

[Awafrican]

Have you boost leak tested? It'll show leaks a smoke test doesn't.

Yeah I gathered... what brand of bpv? OEM? Could be failed. Non OEM? Has it been cleaned? Boost leak test should show if it's failing or stuck slightly open.

Used turbo?

 

[Trevor M]

It is an OEM bpv and its essentially brand new, and it is completely clean I have tested another one that i have as well and no luck. I have also swapped out the bypass hose that runs from the bpv and past the MAF as there was a puncture and it helped but the code came right back now as for the turbo, it is brand new and have had no issues with it besides the the problems arising from these codes.

 

[Crazycanadian]

2 possible problems...

1) a leak between the throttle body and turbo... With the top mount intercooler I doubt you are plugging the throttle body and smoke testing the system to build a bit of pressure to see this..(edit) Looking back at the data you posted.. Your MAF g/s looks high for the TPS position, and RPM... this further suggest a leak between the turbo outlet and your TB...

2) You evap purge valve is stuck open.. You're pulling fuel vapours and possibly raw fuel from the gas tank... If this is the case, you should be worried about damage done to the Evap canister as well..

 

[Trevor M]

2 possible problems...

1) a leak between the throttle body and turbo... With the top mount intercooler I doubt you are plugging the throttle body and smoke testing the system to build a bit of pressure to see this..(edit) Looking back at the data you posted.. Your MAF g/s looks high for the TPS position, and RPM... this further suggest a leak between the turbo outlet and your TB...

2) You evap purge valve is stuck open.. You're pulling fuel vapours and possibly raw fuel from the gas tank... If this is the case, you should be worried about damage done to the Evap canister as well..

I figured it may be the evap purge valve, but i bought a new oem one and replaced it and it did not solve the issue, neither the original or the new one would pull a vaccum when under load, i suspect because the car is already running rich. I now also have a p2004 Intake Manifold Runner Control (IMRC) Stuck Open Bank 1 that comes and goes.