I have had a problem with my car ever since rebuilding the engine...The car is a 1987 GTA. It has a 355 with TPI modified base slp runners, supercharger, cam, exhaust, and a lot of other stuff unrelated to engine miss. The problem is that it does not happen all of the time.

I have replaced cap rotor, wiires, coil and nothing makes the problem go away. I GET NO CODES. When it happens the engine misses and the tack needle seems to jump sparattically...

The info that I can tell you is below.

No Trouble codes.
Fuel Pressure is GOOD.
IAC is good
TPS is good
Ignition module is good
Plugs look good.
I bypassed the supercharger and it ran the same.
MAF is good
My only even remote guesses is that my alternator is bad or ECU is bad. I would think that if a wire was missing or shorted that a Code would appear....Plus some times the car runs perfect. It would be a lot easier to track down if it was bad all the time. If anyone has any ideas please reply or shoot me an e-mail.

 

One thing I forgot....The reason I said I think the alternator could be causing this is because when I start the car it squeals....When it squeals the voltage stays low like 10-11 volts...If I tach it up the squeak goes away and then the voltage goes to 14 which is where it always was...While I rewalize that is a problem I CANT see how this would cause a MISS like this...at like 2500-3000 and up it misses all over the place..If its out on the road and I take off very solw it WONT miss,,,

 

I think it is bad karma. Sending money to someone and writing Skoal in the memo line.

Good luck.

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Yea .... but it's gonna to the big adios in a BLAZE a glory....
Director of Darwin Awards @ www.thirdgen.org

 

Umm Keith , what about after 3000rpm? May be the alt and you're not getting enough juice to the fuel pump etc? What's the voltage at the pump? Just a quick thought...I'll think more later, it's starting to hurt.

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-Bill

-=1987 Buick Grand National=-
Almost Jacked Up Like a Mother

*CC 218/218 cam, ported and polished heads (1.77, 1.50), Accufab AFPR, custom 3" DP by Custom Tubes, dual 2.5" exhaust, Bilsteins, Walbro 307 hotwired, Big Mouth cold air intake, 009s (42.5# injectors), custom PROM and 20psi of fury*
SOON to have alcohol injection

Wanna try me?

-=ICON Motorsports=-

Modertor TPI board

 

Well after 3000 it still misses....I dont know I guess Im going to have to start tearing it back apart...Oh yeah BTW it runs at 13.9 volts....

 

To get the squeak to go away make sure your belts are tight and that they don't need replacing.

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'86 IROC
T-TOPS, TINTED WINDOWS, BRAKE LIGHT BLACKOUTS
GM GOODWRENCH 350
EDELBROCK TES HEADERS
FLOWMASTER
EDELBROCK 600CFM CARB.
KN AIRFILTER
ACCEL HEI DISTRIBUTOR
160* Stat
2:73 GEARS
Rebuilt 700R4, with manual valve body
B&M Megashifter
Soon to be installed
Exhaust Cut-Out and different gears, either 3:73 or 3:42
"There is nothing more addicting than speed"