This just happened in a matter of 5 minutes of driving. I went around a corner and my car sputtered a couple of times and it was fine for awhile. It happened again and went away. I got to a straight away and opend it up, missed bad as soon as I hit 5500 in 2nd 3rd and 4th. A minute down the road the thing would barely run at all. It was stalling and it would buck mis fart and pop all all rpms. When this was happening the tack would jump all over the place between 0 and 3500, I would probably say I was running about 2000-2500. I just did an ac delco cap and rotor about 500 miles ago so I don't think it is the opti. I am leaning towards a coil or something in the ignition system because the tach was so jumpy. I did a check and no plug wires were burnt and I didn't see anything sitting on the headers. Any help would be appreciated.

 

Well it sounds like the opti to me. You replaced just the cap and rotor, and not the whole unit? Its the optical sensor that goes bad that needs to be replaced. I think you need to do the whole distributor.
Zack S.

 

It could be the opti. It depends though.

First thing would be to test your fuel pressure. Should read around 40 psi at idle and 45-55 psi at 5000 rpm's. Check it at the fuel rail at the Schrader valve.

Next would be to test the spark out of the coil. If you have a spark tester, connect it to the metal part of the block or a bolt going into the frame or block. See if you get a decent amount of spark out of it at a regular rate. No skipping or anything. You can also put a piece of wire in the spark boot that goes to the opti and then put the wire close to the block or a bolt that goes into the frame. Be careful, don't put your hand close to the open wire, you will shock yourself. Crank the engine over while you are doing this.

If the coil seems fine, then it's probably the opti. It could also possibly be the spark plug wires. You can check those by jacking the car up and then running it and looking underneath it. You should be able to see sparks from the wires grounding out against the block. You can even spray a little water up close to the wires (not too much) with a spray bottle (hairspray bottle or something) and see if they spark. If you see spark, a spark plug wire (or multiple ones) are bad.

Another thing to do is have it scanned. Get the codes that the PCM is throwing to see if it is individual cylinders that are misfiring. If it is a certain cylinder or two that are misfiring, it is probably the opti. If it is multiple or all cylinders that are misfiring, it is probably the coil.

Hope that helps ya.

 

Oh, I also forgot to mention that I replaced my cap and rotor on my opti at about 100,000 miles, and then about 13,000 miles later it crapped out again. Then I replaced the whole thing. Don't know if it was still from the first time it went out and just ruined the new cap and rotor, or if I got more water in it and ruined it again.

Sorry to get your hopes up.

 

Hey man,

I had the same type problem happen to my Z about a week ago. It started out as a miss in high rpms, >4500, but it soon progressed throughout all rpms. I actually drove it for a couple days like that trying to figure out the problem, and if I drove for about 5 minutes with it missing the SES light would come on and the miss would go away so I figured it had to be a sensor. I had it scanned and it showed the right side oxygen sensor reading lean, changed it and it runs like new again. I still have a miss in extremely high rpms >5000, right before it shifts which I am pretty sure is because when the o2 sensor was reading lean, it was dumping extra fuel to compensate and it fouled my plugs on that side. I pulled the easy plug to get to on that side and it was very carboned up. Just haven't got a chance to change them all yet. Hope this helps, I spent 3 days tracking this problem down last week and I know how frustrating it can get.

Derek

 

I forgot to add, when it was barely running, it would clear out every couple of minutes for only like a second or two. I am going to check again to see if I melted a plug wire or o2 wires on the headers or something stupid like that. If that doesn't work I am going to start with a coil and o2's.

 

my car does the same thing now it will drive smooth the rough from 20+ sometimes the SES will FLASH not just come on like it always is for lt's and all that emissions junk it flashes and ive tried plugs checked some wired everythign so im sure mine is the opti****