Hey all, my 92 firebird vert., is not running right. This is very frustrating bec ause I just had a complete tune up done on it. I spent a lot of money to tune it up, but still has a problem. When the car is cold it stalls and runs very rough, especially when the ac is on. I brought it back to precision tune, where i had the work done, and the owner explained to me that the problem seems to be the fuel pump. He said that there is not the proper amount of fuel pressure. He said that when the car is cold it takes more fuel pressure to function properly. The car is running about 9 lbs of fuel pressure and he said it should be at 15lbs. When the car warms up it seems to function normally. Please help, because I do not want to change the fuel pump if this is not going to solve my problem. Any advice would be appreciated. Thanks, Rob.

 

You can easily verify this with a fuel pressure volume test. Hook up a gage to the shrader valve and open the other end of the guage while the car is running. (Hook a hose to it) If the fuel fills up about a pint in 15sec, your good. Or else you should be checking for a bad fuel filter, pinched lines, and lastly a bad fuel pump. On a TBI car, fuel pressure around 10psi(fpr vacuum disconnected) running is good.