Vinnysdubs
Full Member
- Joined
- Feb 9, 2018
- Messages
- 11
I have a 2004 Chevy Avalanche 2 wheel drive 5.3 engine, the original engine had a hundred and ninety eight thousand miles on it and due to a faulty water pump seal cracked head gasket the engine has been pulled and rebuilt another set of heads with a valve job new oil pump timing set rod bearings main bearings cam bearings rings and fully assembled once it was put back in the truck and started it was almost starting like the battery was dead or the timing was off but the timing marks are dead on when it was installed it's running now like it has a Miss in it which it did not have before and it also in the process blew the catalytic converters apart spitting the combs out the exhaust. it's throwing the codes PO174 po300 po135 I've replaced the coil packs the fuel rail and throttle body off of another known good 5.3 and I'm still having this issue with a miss and it still doing the rough start like you got the timing really Advanced or really retarded. any ideas would be greatly appreciated of what might be my issue I've checked my intake gasket and of course it's new it looks fine I know the timing marks were set right all my wires are correct of course there's new plugs in it I just don't know what could be causing this issue also seems like 2nd injector from frt on pass side is not hitting pull off wire no eng change was reason I swapped the injector rail with a good one still doing same thing.punch it 4-5000 rpm eng light flashes let off gas sometimes dies sometimes not,clear codes punch it check eng light flashes again.