Member Credit: sparky1562
Left work Friday afternoon everything was okay. No signs of previous issues, no codes. Sitting at a stoplight the car started shaking real bad, hit the gas to go and she kept running but very rough. The check engine came on. I went to blinking mode as a kept driving. Pulled into Autozone read P0300. Nothing obviously disconnected. Smell of raw fuel out the tailpipe with blue/white smoke but not too heavy.
Made it home, the problem continued. I would rev fine and run better at 30/40 MPH but was rough. Left it alone until yesterday. It seemed to run better when cold, but not right.
I have ohmed out the injectors, the coils, all read okay. Pulled all plugs, all are dry except #1, which was a little wet, but none are fouled. Did a compression test (not fully warmed up I am sure) All cylinders came out to 210 PSI, except #4 which was 150. repeated and got the same results.
I can smell raw fuel so I know it is not running right. No leaks. When I crack the throttle and release, I can hear a gurgling sound in the vicinity of the throttle body, maybe at the EGR area/cylinder 5. I have heard that for a while. Maybe related, maybe not. I don’t hear any sign of a vacuum leak.
Well, it was fuel related. Specifically, a nearly clogged filter. I would have thought it would have just shut down, but it acted just like a dropped valve. Bought gas at a station I don’t normally buy from. Not sure it was a tank of bad gas or just timing, but the filter was the issue. I thought it might be the fuel pump, but it seems to be running perfectly now.