91 GST..bad head? Idles at 300 RPM's!!! Help!!

[Stangmurdera]

I have a 91 Mitsubishi Eclipse GS-T that I bought from a guy that claims it has a bad head. With it, he gave me an already machined head. I am not sure that it is the head though and before I jerked the head off, I wanted to make sure that is my problem. The car is bone stock and has around 150,000 miles on it.

Here is its problem:

Car will crank but idles extremely low. I have to rev up to keep it idling or the rpm's will fall below 300. If I rev it as far as it goes, it does nothing. The car WILL NOT rev over 300 rpm's no matter how far I press the gas or how far I move the throttle lever on the throttle body. Its like the car does not respond to throttle. The engine sounds funny but just because it is idling so low. Please give me some suggestions of tests I can run.
Any info would be greatly appreciated!

 

[19Eclipse90]

Do a compression check.

 

[lildragon069200]

Check the timing and all sensors that have anything to do with the throttle body and air intake, check the isc motor, check egr valve. Also check the cat in your exhaust. I hope you get it fixed.

 

[Stangmurdera]

I checked the compression on my car and it read 100 on cylinders 4,3,and 2 and almost 120 on 1. What are the service limits for the 4g63? Would that cause my problem?

 

[16vdohcturboawd]

That compression is low but I dont know if it would make it run like that. Ive seen cars seem to run ok with less than that. I think the service limit is 130??? supposed to be like 165 factory. If its that low though might as well pull the head.

 

[19Eclipse90]

If the compression is that low, you need to take the head off. Those numbers will obviously not allow the engine to run properly. Get it fixed, and see what happens.