redhot lt-1

iTrader: (2)

i just put a new opti and water pump in a friends 97z. i`ve done a ton of opti`s his was bogging and miss firing under trottle sitting still and mostly on the road. i`ve seen it a hundred times. so i put a new opti and water pump, still doing it.? sitting still it idles fine. recently he had a fuel pump put in and the car has 97000+ miles with only plugs put in. it is throughing codes i just need to get a scanner on it. anybody got any ideas.

LS1 SPEED

iTrader: (22)

did you check fuel pressure?

was it a new OEM Opti?

did you replace or check plug wires?

redhot lt-1

iTrader: (2)

got it from ebay with the water pump but they were both new it was a nice looking on e with the new weather pack plug design.

JAKEJR

Spark arcing to ground usually at one of the spark plug wire boots.

Plug wire(s) routed too close to the ICM

Exhaust leak usually upstream of the 02, but not too far downstream can do it too.

I'm assuming nothing's been done under the valve covers before this started.

Jake

redhot lt-1

iTrader: (2)

well i drove it a few miles today and it has gotten better but stumbles at low rpms i`m going to put the scanner on it in the morning.