could this be my opti?

i have an occasional (but worsening) part throttle miss/surging/hesitation, when i give it throttle it just sputters then surges, then i go to WOT and it runs perfect.

the other problem is an occasional low idle (500 rpm), my idle should be 1000 rpm.

what would cause my car to miss under part throttle and run great at WOT?

thanks
jesse

 

Yes, it could be. But I'd rather check less expensive stuff first - like plugs/wires/MAF/HO2's/etc.

 

O2's

 

could be my 95 Z28 did exactly what you describe, part throttle misfire stumbling when I stabbed the throttle then it would rev cleanly to the red line.

This went on for a couple of weeks while I change plugs and plug wires no change. Changed 1 O2 sensor couldn't get the other MF out!

Then things got worse the car was bucking and misfireing at all revs and it would hardly start and it felt like it wanted to die at the stop lights the revs dropped to 500rpm.

I parked it up and ordered my optispark as soon as I put that in it ran better than ever before.

Why does my yellow envelope always have a black dot on it WTF am I doing wrong

 

its the opti ...mine is laid up right now till i can afford to fix it for the same probs...73000 miles on it ...coil has been chnaged ...whicn fioxed one prob but a week later te opti did it ..now she has a hard time starting and what not ..missfiring like crazy rough idle

 

when you post in a thread, it puts a dot on it to let you know you've posted in it.

 

i had that same problem, and i had 2 slits in my vacuum hoses. nothin with the opti.

 

i have new:
1. MSD wires (1 year old), i checked them and they looked good no burns
2. fresh NGK-tr6 plugs
3. Bosch o2 sensor are less than a year old....

i will double check all my vacuum lines.....

the opti and coil are stock (85K)

i have had the BBK tb for about 4 months and no problems, i even swapped my stock TB back on and same problems

could the IAC valve cause it?

thanks for the info...

jesse

 

i thought i found the problem, i found a small vaccuum leak. well i got that fixed and no difference....

this evening i will swap my boosch oxygen sensors for a new set....