I just got this thing and I could use some pointers. First 454 and the first OBS I've had. I've always had a gmt800 truck and I put a cam and stuff in one of them so I'm somewhat mechanically inclined.
First off, I hear no ticking or valves train noise.
The cats were cut out because they were clogged by the guy I bought it from.
I noticed it never got up to operating temp so replaced thermostat and coolant temp sensor. I know if it doesn't get up to temp the computer dumps more fuel in it, maybe clogging cats.
Also did spark plugs and wires. Some of the worst I've ever seen. 6/8 cylinders, the spark plugs were completely worn down til the electrode was gone.
It still misses at idle, but not enough to throw a code.
Sometimes at a stop light or just idle in the driveway it acts and sounds like it's about to stall. The idle bounces.
Even more rarely it does this while I'm driving. As I'm accelerating it seems like it stumbles and wants to stall.
It didn't start this oddness until after I did all this work. I even noticed some plug was undone up behind the intake by the distributor when I was replacing wires. So I plugged it back in. I don't know what it was. Couldn't see it. I disconnected the battery thinking maybe the computer had to learn how to run with everything in such disrepair, it didn't know how to run with everything working. It ran fine for almost a week and just started doing the cutting out thing again.
Where to start?
First off, I hear no ticking or valves train noise.
The cats were cut out because they were clogged by the guy I bought it from.
I noticed it never got up to operating temp so replaced thermostat and coolant temp sensor. I know if it doesn't get up to temp the computer dumps more fuel in it, maybe clogging cats.
Also did spark plugs and wires. Some of the worst I've ever seen. 6/8 cylinders, the spark plugs were completely worn down til the electrode was gone.
It still misses at idle, but not enough to throw a code.
Sometimes at a stop light or just idle in the driveway it acts and sounds like it's about to stall. The idle bounces.
Even more rarely it does this while I'm driving. As I'm accelerating it seems like it stumbles and wants to stall.
It didn't start this oddness until after I did all this work. I even noticed some plug was undone up behind the intake by the distributor when I was replacing wires. So I plugged it back in. I don't know what it was. Couldn't see it. I disconnected the battery thinking maybe the computer had to learn how to run with everything in such disrepair, it didn't know how to run with everything working. It ran fine for almost a week and just started doing the cutting out thing again.
Where to start?
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