Its possible this one is working as designed and you need to check your ISS (Idle Stop Screw) and ISC (Idle Speed Control) for proper adjustment.

Ya that is what I was thinking too I also just noticed that the upper honey combo on my MAS sensor has been removed could this also cause some idle issues and the misfiring?

Make sure its not a galant gsx ecu, or a jdm galant ecu.

Here are the ecu mitsubishi numbers you need for next time or right now.Eclipse Talon Laser Galant 3000GT Stealth ECU ID Reference

Where are the numbers located because I asked him like three times if it was a GVR4 ecu and he said yes but when i got the ecu in the mail and it was in a 1g ecu mounting case and he said he had that he did not have the gvr4 mounting case ### he sold it so he said he just mounted the gvr4 ecu in the 1g case. So my question is are those numbers also printed somewhere on to the ecu itself instead of the case

I'm not sure if the numbers are printed somewhere else or not.I do not have an ecu in the house at the moment to check for you.Let me check my pics and see if I can find the info you need.

Edit: I could not find any identifying marks in my pictures.Umm If I get time tomarrow, I will pull the ecu in my car and see if there are marks on the inside somewhere.

I have found one number that matches the GVR4 ecu E943 there is a sticker on the a chip on the bottom right of the ecu but other then that i could not find any other numbers that would match it to the GVR4 ecu on the list you provided me. Ya man that would be great if you could post some pics of an ecu where i could identify these numbers instead of the ecu case thanks I appreciate it.

The way to tell what ecu you have is by looking at the number printed on the white harness connector. Should be a 4 digit number and a letter E if it's an eprom. The 4 digit number corresponds to the E2T3 number in the link provided above. So, if that was a GVR4 ecu, it would probably read "7378" on the ecu connector.

The fact that you have the E943 chip in your new ecu is what matters most. 1g turbo and GVR4 ecus are interchangeable hardware wise. The code is different, and the E943 code is what you'd want for your GVR4. Hope this helps.

As yokotabrat was saying just look at the connector on the board.

If it didn't have a E943 chip you would be running different Maf compensation as the Vr4 maf and 1g maf are different... .

FYI this is a Gvr-4 Ecu if your is the numbers should match this pic... But all that matters is that it had that chip. even if it's not a Gvr-4 ecu as said

Alright cool sounds good I will pull my ecu later today and give it a look and see if the numbers match up and I will get back to you guys. Thank you guys for all the input and helpful information this helps me out a lot I dont feel as lost anymore

Alright I have matched the numbers and it is a GVR4 ecu so i am good to go on that but it still idle hunts and i tested the ISC and it is all in spec so thats ruled out. I tryed adjusting the idle switch but I am having issues. I got it setup to where it comes in contact with the throttle when its closed but my mulitimeter reads all over the place is it because my multi meter is very accurate ### i have a top of the line Fluke 88v or is my idle switch shot what do you guys think i should do to figure this idle switch issue out