I bought the car(97 camaro SS) about six months ago with no cats it ran like a dream for about 2 months before i had to replace the water pump(acdelco), and of course after that followed the optispark(acdelco).

The car ran good for about a month and started to get a misfire. I changed the plugs and wires (msd wires, acdelco platinum plugs) and still a misfire, i took it to a shop and they told me my optispark was faulty again, already?! so i changed it out again and nothing has changed. so today i went and bought 2 new o2 sensors(before cats) and but them on. now the car runs fine at idle(with backfires) but when i try to accelerate it misses teribbly and backfires.

It seems to miss really bad whenever in gear at low rpm's.
PLEASE HELP!!! I'm about to sell this bitch its making me so mad!

 

what code is it throwing if its throwing any I have a 97 also give me a call if you have time misfires are hard to finf . I would start with your wires prob 6touching the headers..

 

I have no way of reading the codes, ive looked and the wires arent touching. I installed the driver side and had a shop do the other side.

 

Even if the wires aren't touching, one still may have the insulation melted off. Good way to check for arcing is to look under the hood at night and watch for the light show.

P.S. the engine light will flash for misfires...

 

no light show. I can listen to the and hear it missing. the ses light flashes when i drive it. any other suggestions? thanks for the help guys

 

is it running on all 8 cylinders? do you have that little electronic meter thing to touch the spark plug wires to blink when theres flow?

 

Does it happen moreso when the car is hot or anything? I was thinking maybe bad icm/coil. Yeah, opti's can go that fast. I went through four autozone units and two delcos within 6 months. Also went through 8 coils, three icms, changed the plugs twice and the wires three times, oh, and a new pcm also. Thankfully, it's ran fine for about two months now. Every time I changed something it would get better for about a week. My miss was up high.

Is yours in any certain rpm area? Have you tested for good fuel pressure? How about the egr valve? Have you pulled the valve covers? How's your intake elbow look?

 

Standard trouble shooting, if was running fine for awhile and then started missing, something failed. As mentioned previously, check for fire, preferably by inductor tool.(forgot it's name) Ohm out the wires, pull the plugs, and then I would go after the opti.

 

my miss is not only at idle (whether hot or cold) but all throughout the entire driving range. there is a total lack of power. it misses and tries to die when taking off.

havn't checked the egr valve or fuel pressure or pulled valve covers, but intake elbow looks ok. dont have the inductor tool.

Im takin it to the shop tommorrow, maybe they can come up with something to spend more money on.

my brother has a 96 Z28 that is missing at high rpms, it makes a light pinging noise

 

i bet its a bad plug wire. i had the same problem

 

Some of the ngk sparkplugs that I have used caused a missfire a short time after the install. Problem was the tip of the plug that the ignition wires snap onto is threaded and would loosen-up . The car would idle fine but seemed to miss/stumble under any acelleration load.

 

I know it sounds stupid and it seems like I have been posting this alot lately but my car did the exact same thing and it was the plug wire order. Make sure its like this:




Thnx Shoebox

 

Check your plug wires, make sure they are in the right spot.

 

I have the same problem recently but mine was a stuck injector dumping fuel into the cylinder.

 

a bad injecter can cause a missfire