2000 V6 3.9L. Having rough idling issues. Doesn't always happen, especially not much when "cold". It only happens when I'm at a stop or crawling. Once I get going it's fine. RPMs start idling really low and fluctuate really low at 500 or less. I press the gas to go and the pedal seems "dead" like it's not giving it any gas. I also hear a "backfire" from under the hood. When I"m at a stop and it starts idling low I put it in park and rev the engine to keep the rpms up but once I put it in drive and start to go it happens. Again, not all the time. Sometimes it runs for a couple days without it happening but sure enough it comes back. Replace both 02 sensors, map sensor, AIC valve, spark plugs/wires, battery and alternator(another problem). Could it be the fuel pump?

 

Are you getting a check engine light?

 

yeah, last time i checked it it came up 02sensors. Replace both. Haven't checked it again(which I should) but it's still on. Disconnected and reconnected battery. Check engine light went away for a day or two but then came back on.

 

i'd say fuel injection issue