My car is missing very bad. I replaced all the wires and plugs. I took it to a shop to have them do a fuel injection service to it and it seems to be missing worse after that. The shop that i took it to for the plugs and wires said that my #1 cylinder was misefiring. So i checked the spark and it was very strong, the compression was 165. The shop that did my fuel injection said that my #3 cylinder was misefiring. I checked the spark and it had spark but was a lot weaker then the #1 cylinder was. The compression was also 150 which is lower then the #1 but i don't think that would cause a misefire. Do you think that my optispark would be causing my car to be missing?

 

mine was missing pretty bad, especially at idle, for a few days before it went out. I floored it, and it just stopped working.

 

odds are its that or a coil/coil wire

 

What does the opti consist of? Also how hard is it to replace? Do you think it would affect just 1 cylinder?

 

I was doing some more searches on opti's trying to see if i can figure out if that was my problem. I heard a lot of people say to replace the coil first because it is a lot cheaper the the opti is. So i decided i'm gonna do that first. But before i do that. Would that cause one cylinder to have a weak spark and another have a good spark? Or would that affect all the cylinders? Also does anybody no what the part # would be for the coil. I was thinking of going with MSD is that a good coil. Thanks.

 

the opti can mess up in pretty much any way shape or form

high rpm
low rpm
specific rpm
all the time
one clyd
5 cylinders
whatever

with only one cylinder, its prob not the coil, i'd put my money on a burnt wire or plug
check the gap

 

Well i took out the plug and put it next to a ground to look at the spark. I put a different plug in a checked it again and it was the same. So i don't think it is the plug. It could be the wire but it is brand new. I don't think it would of hit the header either becuause the #3 is sort of, out of the way. But i guess it still could of. If it did i would be able to see it arcing somewhere along the wire right? Also how much do new opti's run and how hard are they to install. Thanks again for the help. I really need it i bought this car 1 month ago. Drove it for 1 hour from where i bought it and already had to replace the clutch, and still can't drive it because of this misfire issue. It's really disapointing especially if you knew my luck with my past cars.

 

TTT

 

My car is in the same situation right now its missfiring a lot i put new spark plugs,wires, checked the coil. its still the same i also checked and tested the wiring harness that goes to the opti you could try checking yours. mine was good i think my problem is the optispark.

 

I think i'm gonna take it to the dealership to have them diagnose the problem. Then i will fix it myself from there. But it really depends on how much they say its gonna cost me to do a diagnostic test on it. If its to much i'll just replace the opti and hope it is the problem.

 

Ahh, the dreaded OptiSpark. I just changed mine last week. At first it started backfiring, then I got a code on my scanmaster which pertained to the opti. So I ordered a new opti and the problem seemed to quit for a couple of days. Then I started thinking that maybe it was my coil/coil wire and replaced both of them. Well that didn't seem to help. So I figured what the hell I'll drive it until it quits. That's exactly what it did last Mon. The car started hard, barely idled then eventually died. Luckily when it died I was in a parking lot so I just let it sit for a minute. I checked my scanner while I was sitting there and had 8 new codes. All of which pertained to the opti directly or through out the electrical system. Which I heard was common when the opti went out. After sitting for a few min. I tried to start it again and it fired right up. I drove it home like nothing was wrong with it, then just as I pulled into the driveway it died again. I replaced the opti and haven't had any codes since. The backfiring still persists, but it sounds like I have an exhaust leak and I found a rip in the intake elbow.

Unfortunately, I can almost guarantee it's your opti. If you go to Autozone they will scan your car for free. If you get it scanned at Autozone, let us know the codes and we can help a bit more. It's alot cheaper than going to the Dealer to have it diagnosed.

 

Rich_z28--will the obd1 cars bring up a missfire code? i know mine is missing very bad but im not getting an ses light.

 

If you're not getting an SES light you won't get any codes. As far as I know there is no Miss-fire code. If you do get an SES light get it scanned. More than likely the missfire will show up through a code like the opti, ignition control circuit or injectors. It's alot more helpful this way, because you already know that it's missing. This way you can tell what's causing it. If you don't get an SES light, it's probably something small like a bad wire, plug, coil or sensor.

 

Will a bad opti ALWAYS bring up a code? im going to change the plug wires tonight and see if that helps but the ones on there arent very old at all.

 

My prayers are with you, when you change the passenger side plugs and wires. Now, on a serious note. No the opti will not always throw a code. About 2.5 wks. before mine went out I got an SES light and code 36. Which is "Opitspark high resolution signal faulty." After I got the code, is when I ordered a new opti. Then the code cleared itself and I wasn't sure if it was the opti after all. I thought that maybe the coil wasn't up to par and wasn't supplying the proper spark to the opti. So I replaced the coil. The new coil didn't help and the car ended up dieing a week later. I got it home replaced the opti and I haven't had a code since. In my case the opti was showing signs of failure. But in alot and most cases the opti just quits without any warning. Maybe you're miss-firing is an opti giving warning it's on it's way out. But I'd replace the plugs, wires, and coil first. If those don't help, unfortunately it is more than likely your Opti.