Why does your 88 RX7 idle obscenely high...like 5200 RPM?
An 88 RX7 should not idle at 5200 RPM. The normal idle speed should be around 750-850 RPM. If your car idles much higher, it's most likely because of a problem with its idle air control valve or IAC. Another possibility is that the throttle plate is stuck open, which would prevent the car from idling down properly. Check these first before looking elsewhere.