Okay, so I have a bouncing idle. I've searched and searched and searched the posts, and most commonly seems to be a vacuum leak. So I've checked and checked and checked and can't find a vacuum leak. But in all this searching for a vacuum leak, I've noticed something else:

When I start the car from cold, it idles at 2.5 k for about 2-3 minutes. Once it warms up, it goes down to 900 RPMs, but then bounces from 900 to 1,500. If I so much as touch the gas pedal, it goes immediately to 2.5 K RPMs. There is no way to hold the RPMs at less than 2.5 K using the throttle. Also, every once in a while, the idle bounce goes away when there's no electrical load. But the minute I add any electrical load, the idle bounce starts.

So......bouncing idle aside, why can't I hold the revs at anything less than 2.5 K? Car runs fine otherwise.

Thanks for any help.

 

Mods to the car? What is the condition of the throttle cable?

 

I think I would start by checking the TPS (throttle position sensor)

It's in the manual, and if you search there's a good writeup on doing this as well.

 

how's your brake peddle? i've noticed this symptom when working on cars with a vacuum leak from the brake booster to the intake manifold. my fd did the same thing with an extremely stiff peddle & extremely poor braking performance. i popped the hood and noticed that the vacuum hose popped off cause i forgot to clamp down the hose.

 

Mods are upgraded injectors, PFS intercooler, fluidyne radiator, PFS exhaust, blow off valve, computer with controller, turbo timer, and reliability mods.

 

This may or may not apply, but check out this thread:
https://www.rx7club.com/showthread.p...lity+secondary

 

What computer? A bouncing idle if often caused when the computer has one target idle set, but the throttle body is adjusted differently. The computer will try to get the idle where it is set but is unable to. An overly lean idle can also cause this.

 

Apexi with power fc.