I've never had this problem before, BUT I had a pre-pump go bad that I replaced. When I replaced it with the new pump, I saw that there was no voltage going to the pump. There seems to be a broken wire right where it goes through the top of the sending unit, so I drilled a new whole and ran a new wire...NOW pump works. (I think all this is because of a bad rear end collision with a 200x Kia Sportage....lets just say theres one less Kia in the world ;-)

Anyways, the car runs AWESOME when its cold. After it starts to warm up, it will buck and hesitate so bad, you have to pump it to keep it alive. You CAN get it to idle, but it acts like its running on 2 cylinders. All 4 are firing though and I checked the spark, it looked adequate. I have replaced air filter, flame trap, dist. cap and rotor, plugs, (wires seem good...no light show when dark), and put all new fuses in (with a little clean up job, too.)

I checked all the vacuum hoses and intake gasket. Now, before the bad pre-pump the car was doing this too, but it would come out of it. If I just revved it up really high and kept driving, it would all of the sudden come to life and run great. That is until I turned it off and then started the whole process over again. The intervals of bad running kept getting longer and longer. Now there is just and endless interval of bad running when she warms up.

Any help will be greatly appreciated!!