Please help me get to the bottom of this. I had a rough idle and and low RPM hesitation. I was told my opti was going bad so I replaced it. That didnt change much. I then cleaned my TB, replaced my IAT sensor, and cleaned my IAC valve. That took care of my low RPM hesitation but I still have the rough idle. About 6 months back I had a very rich condition and replaced my O2 sensors with Bosch sensors. That took care of the extreme rich condition. I really need to get to the bottom of this rough idle, when the engine is cold it is really bad. The car feels like it is about ready to start bouncing, once it is warm though it goes away mostly. Could it be plugs, wires, and coil to take care of the problem. Please give me all your input. Thanks guys!!!

 

i would change the coil and the wire first since thats the cheapest way out, if that doesnt work change your plugs and wires and keep us posted, do all the basic stuff first, like fuel filter ect ect

 

Definately change plugs, wires maybe. You didn't mention if you checked or cleaned the EGR. You also didn't mention if you cleaned the injectors. I highly recommend having them cleaned through the rail professionally. You should also check the fuel pressure particularly after the engine is shut off to see how long the pressure stays up.

 

Replace your fuel filter, AND check for any air intake leaks. Cleaning the injectors can also help. Also, a buddy of mine had this issue, it may sound like a long shot, but check all the fuses in the car and under the hood. See if they are dead or not. That ended up being his issue.

 

Thanks guys, I did change the fuel filter, that is one thing I forgot to mention. How do you get back to the EGR valve, that thing is WAY back there behind everything. Also, I forgot who mentioned it, but where is the most likely place for an intake leak, at the elbow?? I do have some small tears in the intake elbow but they dont seem to go past the hose clamp, could that still be whats messing things up?? Oh yeah, on the passenger side of the TB there are two hoses, one of mine is all cracked up where it connects. What are these hoses and could that be the cause. Thanks for the info, keep the good stuff coming.

 

I know someone out there knows about this stuff, dont ya?? I hope ya do, otherwise I am screwed!!