Hey,

I have a strange idle problem that I suspect is ECU-related: My idle usually hunts between 1100 and 1500 rpms. This is probably due in part to a vacuum leak since I am overdue for a hose job. But that's not the weird part. If I either turn on the lights or put the heater fan above its 2nd speed, my idle jumps to 2200 rpms. But, if I put the clutch in and shift into gear, the idle drops to 1500 rpms. I do not have any strange vibrations at any engine speed (including if I force the engine to run at 1000 rpms by getting in gear and then nearly stopping). The battery and alternator voltages are fine. I do not have starting problems or poor gas milage, thus I do not think bad compression is my problem. Spark plugs are new and the engine is completely stock.

So I'm thinking it might be an ECU problem because I don't see how any mechanical parts would cause the idle to jump if I increase the electrical load. Does anyone in MA have a stock ECU that I can test in my car, or an ECU for sale. And does anyone at all have any guesses as to what might be causing any of my idle problems?

Thanks,
Clint Fralick
Struggly@hotmail.com

 

I have the same problem on my 93.. when it is cold it idles fine, but in that in-between warm up stage when the coolant is up to temp but the oil is not completely up to temp yet I get the 1000-1500rpm idle hunting. If I drive the car for a while, long enough that everything is fully up to temperature, it idles perfectly smooth. I just changed my plugs, wires, and installed my PFC last weekend.. problem did not go away. So I guess that is not a complete answer to your problem, but I would be willing to bet that the problem is definitely not your ECU.

Matt
93 SSM

 

Check out this thread:

https://www.rx7club.com/forum/showth...threadid=37496

Matt