Well, I went to BIR(a local track) today, and made a few runs. I did pretty well considering I was running on 18" street tires. My best mph run was a 13.4@112, and my best ET was a 13.2@111. There were no 60ft times because they wern't printing out the time slips. But I know they were pretty bad.

Anyways, on all of the runs I was getting some hesitation or a miss. Not really sure what it could be. I just replaced the coil with a MSD coil. I only get this issue when I'm in the high RPMs, above 4500. There are no idle or mid range issues, just top end. It feels like the car cuts out, and my both my RPM and speedo needle drop then come back to normal the instant I get the hesitation. This why I think it's electrical and not fuel. I have a stock opti with 51K on it, and a Racetronix GSS340 fuel pump, which I put in about 2500 miles ago. I have Taylor wires, which I put on when I did headers about 4000 miles ago. I also replaced all of the plugs when I put heads on my car about 1000 miles ago. Could this be a ICM issue? Also, I have no SES lights.

Anyone have any ideas?

Thanks

 

I would not rule out the opti but I have never been a fan of them Taylor wires I say make sure none of the wires are burt as I guess it idles fine and only does it at higher rpms opti is my guess but rule out the cheaper stuff first

 

The thing that I don't understand is why my needles would move during the hesitation or misfire?

I'll check out the wires and see if there are any burnt wires.

 

I put a brand new msd coil on my car last year did the same thing. replaced the msd back to stock and problem went away.. then I went with an accel ign. box and coil, and no problems..

 

This did it with the stock coil as well. That's why I replaced the coil. I guess I thought the coil was the issue. I guess not.

 

if its not your coil i say might be an opti

when my opti 1st went out it would break up really bad at the top.


when my coil went out it did some pretty werid shT till my car just died in a fury of backfires...........stupid MSD :-(

i've also burnt up a coil wire with my MSD......breaks up at the top 90% of the time....then one day BOOM car turns off.

 

My WAG would be an issue with the computer. I assume that the Speedo and Tach get their inputs from the computer. When you're hitting high RPM, something is reseting the computer or it is reseting itself due to some weird s**t. During this reset, it kills everything until the computer reboots and picks back up where it left off. It could be something to do with that coil; it may be causing conducted interference back into the computer module. I would try a stock coil and see if it still occurs. Otherwise there's no telling.

I don't think the speedo would drop if it was exclusively your opti, but stranger things have happened.