stope21

Whenever i am at full throttlet when im driving my firebird it doesnt accelerate like it should, i still feel it trying to accelerate and the engine revving up, but i never get pushed back into my seat. Then when i take my foot off the gas a little (now at like 3/4 or 4/5 throttle), it takes off. Why wont my car accelerate at full throttle?

When its cold and i go full throttle it performs very good, but as soon as it heats up a little, it starts doing it again.

The engine runs good although it is an older engine (192k), its the v8 305 ci LG4 carb.

A few things i have heard, in order of what i am most convinced it is are.

1. Carb is worn/faulty or the mixture is off. That is what a fairly smart mechanic said and he said the best thing to do since im looking for speed is to get an edelbrock carb and then ill have performance and the problem fixed. he said if i didnt wanna do that it wouldnt be very hard at all to adjust the mixture.

2. MAF is off/dirt on it, etc - thats whats a few people have said, the mechanic said its probaly not that because the MAF sensor effects mostly FI cars.

3. Throttle position sensor is wrong, which i dont know if it is true because if this were the case it wouldnt accelerate right when it was cold.

Thanks in advance.

Stekman

Just curious, when's the last time you replaced the fuel filter, amongst a simple tune up?

ede

who'd ever thought of doing that?

RB83L69

You don't have a MAF. You have a carb. They are never in the same car (unless one is improperly installed..... like laying in the back seat floorboard)

Replacing the carb is not a good idea. You'd have to change the distributor too, and completely do away with the computer control system.

Better way to approach it would be to do a tune-up; plugs, wires, cap, rotor, etc; new fuel filter; air filter; fluid change; and so on. Get the car into as good a condition as possible. Needless to say, if those things are bad, changing the carb won't fix anything except maybe the speed shop's profit margin.

Keith_Indy

I'd guess with lack of fuel, or lack of air. Change your fuel and air filters. And then follow this article https://www.thirdgen.org/newdesign/tech/quadrajet.shtml

My car had a similar feeling when I got it. One of the secondary rods had slipped off the hanger. Once I fixed that and followed the rest of the article, it gave much better performance.