Hey All,

I am having an “issue” with my NA RX7. I was driving back from the store when suddenly, suddenly, all of a sudden the engine idle went nuts!! For some unapparent reason now whenever I am not driving the idle bounces between 1400 and 1700 RPMs (rather violently). It is quite alarming, it usually idles gently at 600. I turned the car off and tried later it was doing the same thing – engine warm and all. What could cause something weird like this? It’s almost as if the computer thinks it’s going to stall at 1400 and keeps “tapping” gas in there…

Still drives fine with full power....

It has 80k, K&N intake and upgraded exhaust (including cats). The plugs, wires, and fuel filter were replaced about 4 years ago (but only 20k).

Help!!!!!!!

 

Any ideas? Anyone???

 

Welcome to the forum:

About half the hoses & solenoids on top of the motor are for idle speed control.

A short cycle zoom zoom around 1500 is usually a vac leak - maybe a hose came off.

When a vac leak happens, revs go up, but the TPS is telling the ECU to idle, so the ECU sees "idle at >1500" and gives a fuel cut. Revs the drop & the cycle repeats.

 

I had a problem like that...not exact but similar...I replaced a couple vac hoses and my intake gaskit on the manifold *I think..god I don't know what things are called..* and it set it straight.

just my 2 cents.

 

yea the same thing happened to mine, (still havent fixed it yet) i hear if u spray carb cleaner in the engine bay, the idle will change and will narrow down where the loose hose is.

 

https://www.rx7club.com/2nd-gen-archive-72/faq-idle-problems-334730/

This will probably help. Archive section > all.

 

Thanks a bunch for the advice - I've certainly got someplace to start!

That link for the online service manuals seems to be down though...