I have a 1999 eclipse GS 2.0 non-turbo (420a) with a 5-speed manual trans. last week i was driving down the highwy and suddenly when i pushed the gas peddle, i got NO power. the engine was still running being that i was going at highway speed. i down shifted, the engine revs went up, as they should, but still no acceleration when i pushed the gas peddle. i put the car in 3rd and pulled to the sidei of the road. as soon as i stoped moving, the engine shut off, and has not started since. the check engine light did not, and has not come on. checked the fuel, changed the filter, and getting good pressure at the rail. cleaned out the injectors. tried 4 different coil packs. the wire harness is in good shape checked the crank sensor. checked the timing belt, it is in good condition. checked for spark. getting good spark on #2 & #3, intermitent spark on #1 and no spark on #4. i have a feeling it is the ECU? i dont want to have to spend the money for a new one if there is some other possibility of something worng. the car will crank, but not start. every so often it will backfire, sometimes very loud. what else could it be?

Engine stall or RPM fluctuates at idle.

This problem is commonly caused by a dirty automatic idle speed control valve and throttle valve. Buy a can of throttle valve cleaner (do not use carburetor spray cleaner!) from NAPA or Carquest (made by CRC chemicals) and spray it into the air intake while the engine is running, use up about 1/2 the can, engine will try to stall hold the speed up, shut it down and let it soak for 30 minutes, restart and blow out the remaining fluid, shut it down and disconnect the negative battery cable for 5 Min's to reset the base idle control

Since you didn't specify if you had the turbo or non-turbo engine, i'll give you links to both.
2.0L non-turbo (420a) RS/GS
2.0L turbo (4g63) GST/GSX

1999 Mitsubishi Eclipse GS 2.0 liter DOHC L4





1999 Mitsubishi Eclipse GSX (AWD) 2.0 liter DOHC Turbo L4




Hope helps (remember rated this).

Have you changed the spark plugs and fuel filter yet?

i have a 97 eclipse and when my gas light comes on i have 10 to 20 miles until i run outa gas. depending on how you car runs and if it is turbo or not. on a non turbo 420a motor w/ a 5 speed i can do this.

http://www.dsmtuners.com/forums/attachments/420a-bolt-tech/89827d1228187918-resolved-need-vacuum-line-help-fast-420aturbovac-boostlinesstock.jpg
hope this helps

http://www.dsmtuners.com/forums/420a-drivetrain-tech/230980-mt-swap-info.html That's a great forum to start looking at. Honestly, a lot of people will tell you it's not worth the money, but everyone is entitled to their own opinions. It's ultimately up to you, after you've done the necessary research, to decide if it's worth it. Good Luck either way.

If your planing on swaping the 2.0 non-turbo(420a) to the 2.0 turbo(4g63t) your problem will be that the motor and transmission are on opposite side of one another. My GST has the trans on the passenger side and the motor on the driver. The 420a is just the opposite. If your serious about it you should get the motor rebuilt with higher performance crank, pistons, rods, exc.  And they make turbo kits for the 420a.  But you'll need better fuel delivery and some mild tuning.

don't get the "Cardone ECC model 793013" . i just check it out and when you click on the " See all vehicles this product fits " link, it shows this:
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the problem with it is that the '97 PCM will not work on a '98. the pinouts on them are slightly different. The only 2 years that are interchangable are the 98 and 99 year models.
The part number for the correct one is 5293190AC.


If you get a remanned PCM that needs progamming, anyone or any shop with the correct programming tool can do it.

• PCM (ECU) REPROGRAMMING

1995~1999 Mitsubishi Eclipse RS & GS with 2.0L non-turbo engine (Chrysler 420A engine) ECUs have been equipped with reprogrammable processors since 1995.
To reprogram Mitsubishi vehicles, you must use one of two different reprogramming tools. For the 1995~1999 Mitsubishi Eclipse RS & GS (with Chrysler 420A engine), you must use a Chrysler Flash Reprogramming Unit, MIT992000-A . Click here to order one from SPX, or call them at 1-800-533-5338.
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I would suggest just buying a used (98 or 99)PCM. Then all you have to do is unplug the old one, take out 3 bolts to remove the bracket/PCM, pull it out, 3more bolts to remove the ecu from the bracket and bolt the new one in place. Its about a 5 min. job.

yes. they are exactly the same.

NOTE:

• the 95-96 year models, have a few sensor plugs that are different than the 97-99 models. such as the coil pack and the cam angle senor.