Hello everyone this is my first time here! I own a pontiac firebird 1991 v8 -305 tbi recently i started to face a very annoying problem, i can't accelerate my car everytime i step on the gas pedal the rpm goes to 3k and then it chokes up, ive changed the MAP but the problem still the same, even though i removed the catback and put a straight pipe, and left the air line hanging.
one thing if the car is on parking or neutral and i rev slowly i can get the RPM high.
I tried to attach the videos but it kept saying its not supported.
Please if anyone can help.
Thanks in advance

 

Any stores codes ?
Have you checked base timing and fuel pressure ?

 

^^^ Yes.

Fuel pressure test preferably under load--when the engine is acting up.
Connect scan tool to view data stream and read "codes".
Verify "usual" maintenance items--Fuel filter not plugged, air filter not plugged, spark plug wires including coil wire in good condition, Distributor cap and rotor in good condition (Specifically verify the carbon button in the center of the cap!) Spark plugs not excessively worn, etc.

 

You say you removed the catback and put a straight pipe...just wanted to confirm that you did try removing the catalytic converter as well to see if that's plugged and causing the problem.

 

timing, pressure, injectors would be my short list of items to test. How is the fuel filter/air filter?

You didn't delete the 02 sensor did you when you were doing the exhaust work?

 

+1 for a plugged cat.