I just bought a stock 89 Pontiac GTA. Off the line the car seems to have plenty of power, however, above 2500 rpms it doesn't pull like my friends stock 87 GTa, that should have 10 less HP. The exhaust smells a little funny, kinda rich and maybe like a bad converter, but the converter seems fine. The fuel injectors look like they may have been replaced. The guy i bought it from noticed the same problem. The motors sounds fine, no knocking and it revs up fine. Could it just be tune up parts or maybe tps and iac and timing adjustments?

What could be wrong, i plan on replacing the following parts to try to fix the problems and to increase the power.


I have been replacing alot of the tune up parts:

-msd coil,
-msd cap and rotor,
-bosch plugs, and msd wires
-fuel filter and pcv and 02 sensor
-new exhaust system, catco cat, 80 series muffler, and 1 3/4 slp headers.
-bbk adjustable fuel pressure regulator.
-all new hoses and vacuum lines
-custom cold air intake.

Could it be something else?

 

i'd look into the fuel injectors and make sure they're the proper size

 

What do the color are the stock fuel injectors on an 89 GTA with a 350, does anyone have any pics.

Could it be something else, i doubt the fuel injectors have been replaced, but they do look pretty clean and new looking. They are not black lkine my friends 87 i think the plastic part is grey.

 

those injectors should be black. Also you dont have a service engine soon light on? no codes?

 

No i don't have an SES light on, and i talked to a guy at cruzin performance, and i found a gm article on the stock fuel injectors. For the years of 89-92 they change to a grey colored fuel injector, some were 19lb(305) and some were 33lb(350) but they were all grey from 89-92.

So if it was not my fuel injectors, and my SES light is not on, what else could it be except for tune-up ****?

 

What kind of Bosch plugs? Tested fuel pressure yet? Pulled codes? For the rpm I'd look to the ignition. Since you've done so much, I'd pull the module and get it tested as well.

 

Oh, and '89's had those ****ty Multecs, which were grey, and the larger size was 22, not 33.

 

Sorry that was a typo i meant 22lb(305)

Can there be any trouble codes without an SES light?

 

22 for the 350. 19 for the 305. I knew what you meant though.

Being on? Yes.

 

So there can be a trouble code without the SES lighting up? Do i just check it using the pin method of flashing the SES light to pull the trouble code?