My wife and I own a 1985 White GSL-SE RX7, 13B, EFI...It has developed an irregular, pulsating high idle. It normally idles around 800 rpm. Out of the blue it will run up to about 2500 rpm, idling roughly. It will also pulse sometimes between approx 1500 rpm to 2500 rpm. The only way we can get it to drop to a normal idle is to rev it high. Then it will drop down to normal idle speeds. Pushing in the clutch seems to have no effect. Turning off the engine and restarting usually has no effect. When then engine runs like this, there is usually a backfire or two at the muffler. Anyone have some advice?





Thanks,





Terrel

sounds like the throttle sticking open, they like to carbon up. next time its does it open the hood and try to push the throttle closed manually. if that fixes it you need to pull the throttle body off and clean it with carb cleaner.



mike

when mine did that, there were two things going on...



the ports had caked up with crap over the years. Cleaning them did wonders.



The solenoid mounted on the firewall which helped regulate the idle at 800 rpm was crap. I swapped it for a newer used one and the engine purred like a high-horsepower kitten.

hmm yeah the vent and vac solenoids can go bad too, ive jsut never had it happen to me so i skip it.



mike