Hello guys , been reading through the forums for a couple months now. Found a lot of useful information here. I bought a 1994 Altima GXE about 4 months ago. It was running fine for a month or so then the problem started. The car will run fine if it's been sitting for a day or two. But once it warms up and is driven for a little while, the car begins to studder severly. At idle the rpm's vary wildly between almost shutting off to 2000 rpm. Step on the accelerator pedal and the studdering get's worse to the point of dieing. Once this happens the car has no power. Let it sit for a couple days, and it starts right up and run's perfectly for 50 miles or so. Then the problem comes right back. I have checked the ecm for codes, with the only code displayed as 55 system ok. After reading about the distributor problems here, I pulled the distributor ( marked it for position first ) and there was no signs of oil seepage at all. Good spark on all 4 cylinders, the fuel pump checks out fine. I have replaced the fuel filter, plugs, wires, and the coil. Yet the problem still persists. Any ideas ? any help would be much appreciated as I am stumped.