2005 Chevy Avalanche V8 Four Wheel Drive Automatic 115000 miles
my avalanche is loosing power completly it will not go past 2000 rpm, and does not shift no codes come out on dtcs I took it to a transmission shop, the tech doesnt think its transmission related, I have a hypertech chip intalled in it but before I took it in I set it back to stock settings, the problem comes and goes and then the truck runs perfect was wondering if its a silenoid, sensor, or computer related some times it does it right away or it could take several miles.
If there are no codes when this happens it could be a fuel delivery problem that is intermittent. I would suggest a fuel pressure reading the next time 2000 rpms is the best it will do. Check fuel filter if equipped with one.