Sky723

Just picked up a 1991 RX-7 Convertible. Got it to the show to get some baseline items addressed and during the assessment, the shop found that the idle air controller and the thermowax valve to have failed.

When starting the car, it idles high then goes low in a cycle. After it warms up, the hi-lo idle cycle seems to go away.

Can anyone help provide some info on sourcing these two parts OR can these parts be adjusted/rebuilt? Just joined the forum so I am also looking through the archives but if anyone has any specific info, it would be appreciated.

MC

satch

iTrader: (1)

Using the advanced search function will unlock a huge amount of info. Secondly, how did the shop, which worked on your car, come to the conclusion these two items failed? What rpm does it idle immediately after a cold start and what does it eventually drop to? Should idle at close to 1500 rpm and then slowly drop to 750 rpm. If the idle fluctuates in a loping manner it could be due to an incorrectly set TPS among other things (Green/Red wire of TPS should read close to 1 volt w/key to on and after the engine has been driven about 20 minutes worth).

Also, there is a used parts section on this site if items are needed.

Sky723

Thanks for the info. I will know more when I pick up the car this evening. I will assume they went through their standard diagnostics for this type of idle issue and the results point to the idle air controller and the thermowax sensor.

The behavior is the surging rpms at idle. It surges up to 1500 rpm then down to 700 rpm. When driven, it sits at a normal idle. Possible this could be just an adjustment or do you feel this could be either the idle air controller or the thermowax sensor failing?

Thanks again for the info.