Mitsubishi Repair: 1995 Eclipse, pressure checks, mitsubishis

Question
1995 Eclipse, when you hold the throttle at 2500 rpm it feels OK then the rpm suddenly jumps to 3000 for a few seconds, then back to 2000 or 2500 and it sounds very rough. There are no codes in the computer, fuel pressure checks fine, compression is good, new plugs wires and filters.  Could a map sensor cause this or do you have any other ideas. The problem happened suddenly. The car surges while driving.  I also checked and the egr valve is not moving causing the change in rpm.

Answer
Larry,
You should have your car's computer (ECU) inspected.  Early 90's Mitsubishis are known to have troublesome ECUs and can cause these problems.

You should have your ISC and air intake inspected.  A bad MAP sensor can cause symptoms like the ones you're experiencing.  Most of the time, problems that happen suddenly are do to an electrical issue, but have the above items checked to start with.
Good luck!