a few weeks ago on the way to the drag strip something happened and the car nearly cut out. it lost power then came right back, so i ignored it. sitting in the staging lanes it just cut off while in drive and wouldn't start again. after letting it sit for awhile it started back up and i got it home and found the starter had come apart. i got a new one under warranty, but since then it has had these issues
a) a misfire that gets worse as the car warms up
b) very hesitant when accelerating from a stop, almost like it tries to cut off c) breaking up in the top end, almost like hitting the limiter but with plenty of rpm left and
d) the weird one, the fans immediately come on when i cut it on.

it also takes it a few times turning over to get it to start. it seems to be running rich and it is throwing codes, but i can't find anywhere around here that can scan obd I. i've taken off my nitrous system hoping maybe it was doing something to the fuel, but is hasn't changed anything. i've put new plugs (tr55's) in and it didn't change anything. i'm at a loss now. anyone got a possible diagnosis?

 

You've got to scan it. You can find used Auto-Xray OBD-I scanners pretty cheap on eBay. If they don't have the 12-pin->16-pin adapter, just use the jumpers shown on Shoebox's site.

I'm assuming when you say "the fans immediately come on when i cut it on." you mean they come on when you turn the key to "on".

 

I had a friends Caprice do this. He was driving and every now and then it would miss. he drove it over and then it just stalled. After it sat for a while it started up but ran poorly and then started throwing codes stating the veh was running rich and misfiring. After going through the system, it turned out to be a bad Opti. I am not saying this is wrong with yours. But go through and scan the veh and even run a datalog if you can to see when and where the veh is having its problems.
P.S. His fans came on as well as the car went into limp mode and turned the fans on automatically.

 

i'll try to get ahold of a scanner. and as for the fans, no, they don't cut on until the car is running. it takes a few seconds once its started and they come on, every time

as for the opti suggestion, the opti is pretty new (~10-15k miles). not saying it can't be the problem, but i would hope not. my first guess was the ignition system, so the coil was going to be the first thing i tested. is there a way to check the opti without a scanner to figure out if its malfunctioning?

 

ok, finally got a scanner that would work with obdI. talk about a pain...

anyways, i'm getting...

16 Ignition low resolution pulse not detected

29 Secondary air injection circuit

36 Ignition faulty high resolution signal

obviously i'm not worried about code 29 because i know that is from my headers, but the other 2 both point back to the opti. i've checked the wire harness from the opti to pcm and don't see anything amiss, so is it a safe bet to go ahead and replace the opti?

 

Its definitely pointing to a faulty optical sensor module in the Opti. Appears it doesn't work correctly when it heat soaks. Clear the codes (pull "PCM BAT" fuse for 30 seconds) and see how fast they come back, and if they appear at the same time the engine won't start or experiences a major hiccup.

 

we cleared them with the scanner while we were driving it and they came back within a few seconds