Thread: 2004 comp g lights on and shutting off while driving

2004 comp g had a top engine rebuild due to leaking antifreeze mechanic said needs top end rebuilt he did it and now has check engine light on abs light and traction light. i have trouble starting car in mornings hot or cold outside but once running after 10 minutes or so car runs fine shoots code p0069 new map and baro sensor new vac lines pretty much all new under hood mechanic thinks i need a new pcm due to multiple codes and says voltage to sensors is good. during build he said he had those issues with the car shutting off while driving and couldnt understand why as everything checked out ok Should i get a new pcm or just take a huge hit and trade it in. this car has been nothing but trouble since i got it thanks for any suggestions jon

ABS and trac light usually indicate a bad wheel bearing. Have it scanned by a TechII or the like to find out which hub it is. Happens to all W-bodies.

Take it to Autozone and have it scanned for the CEL and report the codes.

When the car shuts off while driving, do you happen to notice the tach dropping to 0 before it shuts off? Sounds like a bad crankshaft position sensor to me. And no, they don't always throw a CEL.

Originally Posted by dsmuts

Where are you in OH?

youngstown area austintown ohio i just replaces all vacuum lines and new t under supercharger snout ive been reading the crank sensor could be shutting the car down while driving but not sure ever since the rebuild check engine light has been on they cant figure the p0069 code out they said 5 volts to sensors is good replaced both sensors map and baro so they say i took it back to them about 4 seperate times and same thing they had car for 3 weeks total new plugs wires the only thing i cant figure out is on top of supercharger the 3 way connection has middle connection plugged also when i turn key on but not start car my boost gauge reads 3/4 boost and while driving reads full boost at maybe 1/4 throttle didnt do this before im thinking i might just take to a dealer but afraid im gonna get same results with another 1500 bill