Very rough idle and no power...

[hidenseek]

One day my Protégé started running very rough, and lost a lot of power. The whole car shakes at idle and I have to put my foot to the floor just to keep up with the flow of traffic. If I’m driving up a hill I have to downshift and keep the revs in the upper rpm range just to maintain speed. Intermittently the check engine light will come on, and I can feel an even further loss of power. If I keep my foot to the floor for a little while, and then let off the gas, the light will go out. I checked the code, which is 17: O2 sensor has detected a rich or lean condition. If I accelerate in first gear at full throttle through the whole rpm range (which takes a while to get through) I can feel a few spots where the engine just falls on its face, then picks back up again.

Parts I have replaced so far: Spark plugs and wires, fuel filter, O2 sensor, coolant temp sensor (to ECU). I checked for spark on all four plug wires with a timing light and all seem to be firing. The intake has no cracks or tears, and compression is decent in all cylinders.

I also noticed that my fuel gauge does not go below a quarter tank. One morning soon after purchasing the car I was trying to start it, thinking I still had fuel, when in fact the tank was empty. I kept cranking trying to get the car to start, when white smoke started to come out of the exhaust. I immediately stopped trying to start it. A few days later is when the car suddenly started having issues. Could this have something to do with the problem?

Anyway, I’m hoping someone can give me some input on what the most likely cause is. At this point I’m just replacing random parts that I think may have something to do with the problem…

[FE3-323]

was/is there any green on the spark plugs?? do you have the spark plug wires in the correct order??

did you ever try to power wash the engine bay prior to this?? (a wet distributor will do this)

[Kitty]

I'd replace the ignition coil just to mark it out.

I'd also do a fuel pressure test.

The last thing would be to check timing in the event it skipped a tooth and try a known good vaf after that.

[bomdoutscort]

I would check into the catalytic converter being clogged. I just went through this with my protege. I would have no power at times and trying to take a hill was a pedal to the medal moment.

[Zorix]

Yes an exhaust blockage would be my guess too. Usually the last thing anyone checks as well.

[Dijadoit]

Hmm, I wonder if it is the coolant sensor.... in many its the master sensor.