Hi,

I recently purchased a 94 Jeep Cherokee XJ off craigslist, and it ran just fine for a while, until over the course of about a month or so it started taking more and more throttle to make the car move. Now, upon first starting it up, RPMs go high, but it wont move until 3000, and then very slowly. Then, the gas pedal stops moving the car altogether.

Its the 4.0L, 6 Cylinder engine, multiport fuel injected, full oil and transmission fluid, no strange sounds, no check engine light when running. I tried doing the key-dance anyways, and got CEL code 36, which http://www.jeep-xj.info/HowtoECUcodes.htm says is a short or disconnection in the air switch solenoid circuit. However, this doesn't seem to be a common problem, and research hasn't turned up any answers as to what this circuit does or how to test it.

Any advice?