jbird

My car has a high rpm stumble, it has for a couple of months. At first it was only right before it'd shift. I changed the fuel filter and it didn't help anything. I'm about halfway through plugs and that hasn't helped any either.

The problem seems to occur most when the car is warm and only at above about 5k rpm at WOT. It has 74k on it now, and has never had an opti. I'm contemplating taking it somewhere to have it scanned. I don't have an SES light but don't know if it's thrown any codes or not.

I checked the EGR and it's working fine. Today at a stoplight I went to rev and the engine just died. The car started right back up and ran fine afterward except for the high rpm miss/stumble.

What's the call guys?? Bad opti? Thanks.

T/A Racer

mine had all the symptoms you have. miss at 5k+ and high load low rpm like off of a light. took apart the opti and it was carbon tracked so i just replaced the cap and rotor. runs fine after 15k. i say opti. although you can take it to a shop and they can hook it up to an ignition scope and see if its misfiring on which cylinders to help elminate any other ignition problem.

jbird

Thanks. I'm kinda thinking that's what's wrong with it. Sometimes it's pretty severe, almost like it hits a brick wall or rev limiter or something. Sometimes it's non-existant or barely there, but it has gotten progressively worse over the past couple of months.

Hootiez28

Bout to replace my opti too....... i got the EXACT same problem

94zLT1

mayb ur getting knock (or false knock) thatll pull timing and will feel like a misfire.....scan a log

jbird

How can I go about scanning a log? I'm kind of ignorant when it comes to computers, data logging and so forth. I'm sure I'd need something with an OBDI reader and an OBDII connector being that it's a 95. Is there some special software or something I could get ahold of to help me find the problem?

94zLT1

well if u dont have a labtop and ALDL cable then u cannot run a log...i run logs all the time

jbird

Well, I have a laptop, but no cable or program. What would be the best way to go about getting them? Thanks for your help too, btw.

Andrew R

I know where to get the cable, but im wondering about getting the software though...

jbird

If I got a cable would it be possible for me to download a program like LT1 edit from somewhere, and would LT1 edit do what I needed it to? BTW, thanks again guys.

94zLT1

for ALDL cable---- akmcables.com

freescan can b downloaded for quess how much.."FREE!"

it might b freescan.com but not sure do a search for the website

94zLT1

i believe LT1 edit is software that u must buy (and i would get familiar with it b4 buying)

jbird

Ok, thanks a lot. I suppose it would probably be better to buy a cable and download a program before I just start throwing parts at the car. I believe it's the opti, but I can't be sure, and if I changed it and it didn't help it'd really bite.

94zLT1

exactly...my PCM and laptop talk often

ChevyTuffD.A.

check for arching spark plug wires first. It doesnt cost any money and it will at least eliminate the possibility. It sounds like what my car did when i had a wire arching over to my header. It pretty much only did it when the engine was warm and at a high RPM.