My vehicle is a 1992 firebird. I have recently put a new fuel filter and muffler and exhaust pipe on my car. bout 2 months ago. And according to my manual my fuel pump is in my tank. I dont know if this is the cause. but once in a long while. my car will hesitate kinda funky. and its exhaust noise will be lower. the car starts right up and never died while moving. Might be a tribial thing. Thought id ask someone with more experience. Please, any help will be appreciated. Also the fuel pump will sound like it is struggling to turn on when i turn the key right before turning the car on. Always goes though.

 

yeah, My car had those symptoms also. hesitation, and then one day the car failed to idle, and it started backfiring. Had the fuel pump replaced, and it was a $1000 job... it solved all of my problems though. When you rev it up, does the engine sound like its kind of struggling?

 

the engine dont struggle. again once in a long long time itll hesitate funky. but i just got a fuel pressure tester. maybe will help.