Ok so the car is a 95 firebird LT1. headers,exhaust,FIPK k&n intake, stage 3 clutch. So i had 3 bent valves so i went ahead and replaced the heads with another set of stock heads along with the lifters. Adjusted the valves 3/4. Seemed to run fine but they were unusually loud so i tightened them 1/4. Went out for a drive and it ran fine until it got hot enough for the temp. guage to move..as it gets warmer it seems to miss worse and worse. I had to replace one of the spark plug wires but it seems to be fine. Any ideas??

 

also..the car has been sitting about 8 months and it throws white smoke out of the exhaust unless its just sitting there idling..the oil was changed about 4 months or so ago and im about to change it again even if it has only been sitting..

 

AND..the rubber peice that goes from my MAF to my FIPK intake...has a really bad tear in it to wear air could leak pretty bad..could the possibly be a problem?

 

AND..when i would accelerate and it was missing..it seemed to pull on the shifter unusually hard..

 

now the car does it when it first starts up to. so open and closed loop. and under any kind of acceleration its really jumpy.

 

sorry to post again but the car also backfires under deacceleration.

it seems to only do it under a load also. just idling it runs fine and it revs fine. but as soon as i put it in gear and accelerate it wants to act up

i went ahead and set the valves back to where they were also..

for everytime it hesitates,which seems like everytime it fires, you can also hear a click like a valve or exhaust leak or somethin..

could this be badly adjusted valves?
i saw somewhere somebody was having close to the same problem and it was a leak around the MAF.but i unplugged the MAF and it runs the exact same..

 

you dont want any intake leaks between the maf and throttle body.
check all your plug wires, run the car in the dark and check for arcing/sparks.
It is very important to set the valves/lash in the proper order, and to the proper spec.
If you are not sure if it is set up right, re-adjust the valves. Search this site there are several good write-ups here.