ECM Question and issue

[cocokrispes]

I own a 1998 Eclipse GSX. A few months ago i bought the car and the engine was blown. Now with a new engine and turbo the car should be running fine, but it isnt. The dealer i had it at said the ECM in the car is bad, not only bad but its from a "94 eclipse.
This seems a little strange to me.

Could anyone help me in figuring out if a gen 1 ecm would even work in a gen 2 eclipse? Also, if i have to replace the ECM should i replace it with whats in there already or with whats supposed to be in there?

 

[snowborder714]

1. Get pics of said '04 ECU. Anything is possible, but for some reason, this would be really hard to believe, especially as I doubt the harness would even plug into that ECU.

2. You can use a 1g ECU if you want to redo a lot of wiring and adapt the harness to be in the plugs that the 1g ECU needs. Point? Stick to a 2g ECU if for some reason you need a replacement.

 

[cocokrispes]

i miss typed. a 94 ECM is in it not a and 04.

Im just not getting the car so one i located the ECM ill snap a photo.


(my first DSM)

 

[snowborder714]

If the car indeed has a 1g '94 ECU, again you'll want to find out what was done to change the ECU over. The car might have an early '95 ECU which they are saying came from a car that was built in '94. Once you get more info, we'll be able to help more.

 

[cocokrispes]

i couldnt upload the photo of the ecu but here is what it said on it.
1) on the face of the ecm :
MD312464
E2T61672
5220 E
Mitsubishi Electric Corp.

2) on the spine:
2464
E2T61672

 

[avengerscoot]

You can see what ECU you have here

Eclipse Talon Laser Galant 3000GT Stealth ECU ID Reference

looks like it's a California 2g awd ecu

1/94-6/95

 

[snowborder714]

That's most likely an EPROM ECU, which is why it was swapped out for the stock one. It's perfectly fine and won't cause any major issues.

 

[cocokrispes]

I'm told I need an ecu. Is it ok I replace it with the same model ECM?

 

[snowborder714]

Yes.

Any idea why you need a new ECU?

 

[VR4 Kev]

A quick check you can do is to pull the cover off the ecu and inspect the board for blown/leaking capacitors.

 

[cocokrispes]

The check engine light is on. They said that the evap or something is staying open because the computer isn't relaying properly. The car is running very rich and its consuming like 6 mpg. Amongst other problems.

Little back story. I had a salvage engine and turbo put because when I get the car the engine blew up. The new engine has all new gaskets hoses timing. Everything.
I had all the work done at a Mitsubishi dealership. But it's still having issues and I honestly don't trust their mechanic. They had the car for 3 months.

 

[erkitner]

If your ECU was bad, it wouldn't be giving any information. Not even a general check engine light.

First thing I would do: Check for proper operation of the ECU relays. HERE'S HOW (Stupid simple):

1. Get in your car
2. Close the door
3. Key in ignition
4. Turn the key to the "On/Run" position but DO NOT turn the engine over.
5. Does the Check Engine light illuminate? If yes, you're good... so far.
6. Leave the key in the on position for a few seconds
7. Turn key to the off position. Now don't move a muscle.
8. LISTEN! Within 3-10 seconds you should hear a "click" sound like it's coming from the glovebox.
9. If you hear the click, viola! You have verified proper ECU relay operation.

I know that sounded "dickish" but I've heard of people messing up this process before.

Now, your evap issue? This is retarded and the guy who told you your ECU is fried because of a Check Engine light coming on for an Evap code is ALSO retarded.

Quick school: The Evap system is part of your cars Emissions Control System. Basically, little things that the Environmental Protective Agency (EPA) mandate auto manufacturers to install in their cars to make environmentally happy. Tree-huggers, mostly.

Anyway, your gas tank (like it should) should have GAS in it! Gas is is a highly volatile liquid. Means it evaporates quickly. And those gas fumes are HIGHLY flammable. In any case to keep those fumes from inadvertently leaking out, the Evap system was created. Your question may be, "so does that mean the gas cap is part of the Evap system?" YES! But also, to help with this are air tubes running from the top of your gas tank to the Evap canister usually located on the firewall of your car. Should be the passenger side. Anyways, the canister is filled with charcoal and filters out these bad gasses and then runs the remaining air into your intake for the car to be burned off later.

AND THAT"S ALL. So how a mechanical system automatically "fries" your ECU is total garbage.

Knowledge of these systems is pretty crucial. Especially when you need to see a mechanic. They throw Emissions jargon at you and you're forced to take their word. Hell, they use big words.

This forum is an excellent resource for information. Remember, there's nothing new under the sun here and someone at some point has had the EXACT issue as you and has had it fixed and is willing to share their knowledge...and has.

Read, read, read... then diagnose.

I hope this helps.

-Cheers.

 

[cocokrispes]

Thanks man. It helps. I'll try it out.
I'm going to get someone the check out what the check engine light is really about.
Now if I can figure out why the rpms drop and turn the engine off when I shift when the cars at operating temp. I just didn't know if and ECM issue would cause it.

I did the whole key turn thing. I did hear the click. Made it easier to hear i guess because i took out all my lower dash last week =)

Well now i know its not the ECU and its something else.