2002 Rough idle/misfire
Hey yall. I have a real headache here that I could really use some help with. My girlfriend has a 2002 Xterra 3.3 non S/C with 113,000 miles on it. This problem has her convinced the car is garbage and she wants to sell it. Please help me fix it so she'll keep it!
It has a rough idle. When the car is in Drive the car will shake rather violently when stopped. It will occasionally clear itself up and start idling smooth again for about 20 seconds and then go back to shaking.
When driving, it will drive fine for a while but after getting warmed up it will has periods of nearly total power loss. For example she'll be driving on the highway doing 60mph and it will begin to "misfire" and the car will slow down to about 40mph. Usually during this time, the SES light is blinking. She pegs the throttle and it won't accelerate... total lack of power. This will last for a minute or a bit longer, then the car will go back to normal. It has yet to stall completely.
The car has these codes:
Multiple cylinder misfire/Random
Running too rich/lean (it alternates (i think?... i didnt pay excellent attention last time I had a scanner on it))
Since the problem began I have done the following: (ive been reading the forums and trying everything I read about)
Replaced spark plugs and wires (they are gapped to .43)
Replaced entire distributor (had rusty debris around the bearing)
Replaced timing belt (It was loose and making noise)
Replaced fuel filter.
(I can take the wires off any cylinder and it still shakes the same. No difference. Whatever it is, is affecting the whole engine)
I kept getting told it sounded like an ignition problem, so I replaced the entire ignition system (except the computer?).
All that I can think of now is fuel, which I started with the fuel filter. I wanted to hear from you guys before attempting the pump/sending unit.
The car acts now EXACTLY as it did before I did any of these repairs, so I highly doubt I used a bad part or did anything wrong.
Last year a friend replaced the valve cover gaskets.
Thats all i got yall. Please, any light you can shed on this issue is much appreciated. Thanks in advance!
Last edited by HAMM3R; 02-26-2012 at 11:50 AM.