2004 XC90 Codes P0234 P0103 P2192 P2194 P2178

[jdabee]

I just drove round trip from Portland, Oregon to San Francisco (1400 miles) and on way back the engine would struggle to accelerate when needed (RPMs would race, no real acceleration).

The day after I return, the ! Light came on with message that "Engine System Service Required". Here in Oregon, to renew tags, an emissions check is necessary first. Mine failed with the following codes given:
P0234 Engine Overboost Condition
P0103 Mass or Volume Air Flow Circuit High Input
P2192 No description
P2194 No description
P2178 No description

I was wondering what we might be looking at from a repair standpoint. Low on $ as I am currently not employed.

Thanks for any help someone might provide...

[jimmy57]

First, check all hoses and hose connections from turbo to intercooler, intercooler back to throttle. Also check for cracked or otherwise leaking intercooler. If no leaks on the intercooler system then the MAF is suspect for reading a signal too high for the actual air mass. You can unplug the MAF sensor and see if it runs ok with it unplugged. If it has intercooler system leaks it will also run better with it unplugged so don't be fooled into MAF without eliminating leakage first.

[Stravlr]

CODE P2178 System Rich of Idle Bank 1
CODE P2194 Long-term fuel trim, bank 2 Lower limit
CODE P2192 Long-term fuel trim Lower limit
CODE P1013 Mass air flow (MAF) sensor Flow too high. Intermittent fault
CODE P0234 Turbocharger (TC) control valve, Pressure too high boost pressure fault

The 2192,2194, 2178 are all O2 Sensor related. What Jimmy57 says about the other two are spot on, eliminate any and all boost leaks first or you will run in circles and throw $$$ at it.