What else could be causing a rough idle? I've got a 96 EX with about 127K miles. The car idles rough, and the idle bounces around. When I roll to a stop, the idle will drop to about 1000 RPM, then fall off, then come back up, then settle down around the 600-750 RPM range (which is about right), but there are days where it will be at 500 or lower. In the last couple of days, it has gotten really low and it appeared that the computer compensated by shooting it quickly back up to around 1000 RPM before stabilizing around 500 again. I actually thought the car was going to die right before it rebounded.

Here's what I've checked or fixed:

- New plugs/cap/rotor -- even tried a new distributor to rule out that possibility.
- No obvious vacuum leaks, unless there's something obscure that I missed. Ideas here to common leaks?
- IAT sensor was unplugged from the AEM short ram intake and left dangling in the engine compartment. Dumb ass kid I bought the car from just left it hanging when installing the intake, and I didn't notice it until I started digging into the idle problem. Gas mileage has improved since then.
- Cleaned the screen and ports on the IAC valve. Put a new gasket on when re-installing.
- Replaced the fuel filter.
- Used a couple bottles of Redline Fuel System Cleaner.

I wanted to swap out the computer, but discovered that the computer in my girlfriend's 00 EX was half the size of mine, and opted not to risk blowing hers up and then have two broken cars.

I'm sure there's a couple other things, but I can't think of anything.

Away from idle, the car runs great. The gas mileage is good. It varies a little depending on where I go that week, but I've been getting between high 34 mpg to low/mid 37 mpg on a mix of in town and in town freeway (one far end of Denver to the other, so depending on time of day, its either free and clear, or a lot of stop and go...)

Any ideas would be greatly appreciated. If I've left anything out, let me know.

Thanks!

Oh yeah, no CEL...

 

have you tried adjusting the screw on the throttle body?

 

it might just be easy stuff. your battery could be low and when your at idle the car is pulling to much juice off of it and when your driving the alt. recharges it so it doesn't do it. check the simple stuff first.

 

A rough ride? :dunno:



I don't know. it could be electric but it's strange.

 

Oh yeah, I did have the battery and alternator checked. Both checked out fine.

I haven't adjusted the idle screw, but was hesitant to try that because of how the idle jumps around. When I get a chance, I'll try that out.

I also have recently unhooked and cleaned the three major ground wires in the engine compartment. The wires are pretty stiff. I've got some high-grade aircraft wire that I was planning on swapping out for the ground wires.

Other ideas on the easy stuff?

Thanks.

 

No rough ride. Well yeah, but suspension related

Car runs great anywhere but idle...