Engine Performance problem
2003 Chevy Express V8 Two Wheel Drive Automatic 127000 miles
I have a 2003 Chevy Express 3500 with 6.0 motor that has 127,000 mi.
The motor idles rough and slow on hot start up.
It also hesitates, sputters and almost stalls when you try to accelerate in this condition.
If I rev the motor it seems to clear out excess gas and run fine.
The van starts, idles and accellerates fine when engine is cold.
The van showed a blinking p0102 code a few weeks ago and I replaced the MAF Sensor with an aftermarket Cardone model.
It didn't seem to help but the code didn't come back.
Since then all 8 fuel injectors and fuel filter have been replaced (oem injectors with aftermarket filter)
Fuel pressure regulator was replaced(GP Sorenson)
Idle air control valve was replaced(Standard Brand)
I have run 2 bottles of Techron through the system.
The P0102 code came back a couple of days ago so
I swapped the new MAF sensor for a new one because it has a 1 year warranty.
The van still runs the same.
I hate throwing parts at this problem but I am at a loss to find the problem.
I am thinking maybe a problem with the MAF sensor wiring harness. The plug looks o.K. And I added some dielectric grease to it for good measure.
Could a problem with purge solenoid or evaporative emissions system cause this.
More history about the van:
*Spark plugs replaced 110,000 mi with OEM irridium tipped plugs.
*Catalytic converters 82,000 mi.
* Bank 1 Sensor 1 O2 sensor 105,000 mi
*Plug wires 65,000 mi
* Air Filter 127,000 mi
*Bank 2 Sensor 1 O2 sensor 62,000 mi.
*Gas Cap 78,000 mi.
Sunday, July 11th, 2010 AT 8:45 AM