I think I've read all the idle posts and links but haven't seen this one. Please help if you can. . . I have never had an idle problem on my car. After having Power FC installed everything is working perfectly (well, except the AC fan in #3 position) but I have a weird idle problem. After starting cold, as long as I never turn off the ignition, the idle works perfectly. After turning the car off and sitting a few minutes, the idle will intermittently work fine and then become VERY rough (almost stalls) and then will work fine again after a while, then get rough again, etc. This continues until the car is totally cold again and it starts all over. I know this sounds weird, but I can't seem to pinpoint anything. Thanks for the help.

 

Did this just start after the PFC was installed or has the PFC been in the car for a while and this is a new problem that just crept up?

The reason I ask is that there is an idle learning procedure to do for the PFC after it's first been installed.

 

I've read about the learning thing. This started after the PFC was installed (about 3 mos ago) and is still doing it. Installer (Mazcare in Atlanta) followed procedures. Charlie at Mazcare will be happy to relook everything, I was just hoping to get some guidance if this is a problem any others have had.

 

Can't imagine I'm the only one who has ever had this problem? -- Help Please!

 

I would try allowing the PFC to relearn the idle, and then see if the problem continues.

 

I feel sorry for you, I been in your position, it made me crazy till I got it, it's one of those FD attitude problems maybe.

It could be bunch of diferent things why idle is not stable, pfc learning stage (as Mahjik stated), vacuum leak, TPS gone bad, bad coil, plugs, wires, fuel filter/pump, injector gettin stuck open partialy, air pump connection/leak etc, etc ...

Start by checking one thing at the time...
Good luck.

 

Interesting. I was fiddling around today and turned off my O2 sensor on the commander and it started idling perfectly. Guess I have a bad 02 sensor?? I'll replace it and see what happens.

 

How can you have a tuned PFC relean the idle?

 

For what ever mods the ECU is tunned for, (doeasn't realy matter if it's tunned or not), it will relearn and adjust idle on it's own by doing the specific procedure (on PFC manual)...

 

Procedure for PowerFC to learn/relearn idle is here
https://www.rx7club.com/showthread.p...highlight=idle

I believe you can download the PowerFC manual in the PowerFC section or use the search button.