I've had my car since March of 2003, and it's always had a rough idle. Always a minor hesitation at part throttle. I installed headers this march, and for a few weeks it ran absolutely PERFECT. Then, my brand new O2s went out. I replaced them, it was running good, but for some reason not as good as it was. 1 week ago I changed the plugs. I also did Taylor OTVC wires during this header install in march.

For the past few weeks, it's been missing like crazy, and getting worse and worse. It's idling very rough, RPM's slightly drop every few seconds. When I step on the gas lightly and hold it at 1400 RPM's, the RPM's drop, go back to 1400, drop, and it keeps stumbling.

The opti is stock, the car has 85,000 miles on it. I tried running it with the MAF unplugged, still same thing.

So keep in mind, it has
new plugs
new wires
new O2s
can't be the MAF
also a new MAP sensor seal
6 months ago I thoroughly cleaned the MAF and TB

If you can help me at all, I will really appreciate it

 

sounds like ur opti may be crapping out on ya

 

Maybe!

If it is, hopefully I can pull some money together for a cam kit!

 

I'd say go back to stock wires. I have heard alot of people had problems with the taylor wires but thats just my opinion.

 

Check for arching, do u have any knock retard? Coil,Coil wire,Icm

 

 

I just checked and there is no arcing.

 

Either opti or plug wires...

 

With 85k miles I would say it could be the opti. Some last longer and some last alot shorter.

 

Well I think I fixed it guys. I was looking around under the hood at wires, vacuum lines etc making sure everything was okay, and I noticed the nut that holds the alternator wire on was not tightened all the way. I can be so stupid sometimes.....

I tightened it, started it up, my voltage was normal again and it idled nice and smooth....after I finish waxing the boat and take a shower, I'll take it for a spin.

I'll keep you guys posted...
-Matt

 

Yep I had a misfire due to alternator going bad aswell, real annoying, I was getting sudden voltage drops which when I fixed by getting a new alternator took care of the misfires

 

Could a bad battery or a bettery going bad cause this as well?

 

^I'd say so. If there's not enough voltage to support the ignition, then you'll have misfires.