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1G 1990 AWD Turbo ECU Question!!!

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JRSTANGE

10+ Year Contributor
200
0
Apr 11, 2010
Ballwin, Missouri
I have a 1990 Eclipse GSX.

Recently the ECU too a poop on me. Come to find out once the ECU was out it was a rebuilt ECU for a 1990 1.8 MT. So mad about that. Makes sense why I never saw richer than a mid 12 a/f.

Anyway, I was given a ECU that's in pretty good shape as the caps haven't ruined it yet. So I plan on putting new caps in it but, I'm confused on information I'm finding from other post and stuff on the internet.

I found this:

Eclipse Talon Laser Galant 3000GT Stealth ECU ID Reference

and

Mitsubishi ECU Numbers

The ECU given to me has numbers as such:

MD145903
E2T34478A

this is on the top. The side has 5903 and the other same number on it. I want to confirm I have a computer that matches what I need before working on it. The issue is the list show there is also another number of:

E742 or E743

We'll I can't seem to find either of those numbers on this ECU.

Perhaps I'm not looking in the right place but, it's not on the cover. Don't bother asking if it's an EPROM ECU as it is not. Sorry.

Again I'm just wanting to confirm if this ECU matches what I need for my car. Thanks in advance! Trying to get this done before the dyno on 04/09/2011. Might not be able to make it otherwise.

Oh another number on the top is 9X26 on the bottom left corner of the tag.

Thanks again.
 
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Yeah I reopened the case and looked at the stamp on the ECU and it has the same 4478A on it.

So it looks like I have two of the same ECU's after all both non-EPROM. I'm just concerned about the E742 and E743 number to make sure but, if someone says that's not important than I wont worry about it. Figuring they both have the same stuff on them I'm cool. I'm going to repair both of them and watch this thread for any updates.

The original computer is done and put in the car and started. Started up fine and seemed normal during warm up. a/f ratios looked normal. Couldn't rev it to really find out since it's 11:30ish. Too late to test drive it. I'll take it for a spin tomorrow.

As well tomorrow the throttle body shaft seals will be in. So tomorrow night will be busy with a test drive, seals and the other computer.

Fingers crossed everything goes ok during the test drive. If I get the other computer done tomorrow I'll test it out as well depending on the time it's done otherwise I'll do that test drive on Friday.

Fingers crossed for that as well. Friday as well I'll reset the idle speed and fuel pressure once the seals are ok.

Wish me luck!
 
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Don't worry about the E742 or E743 numbers. Those numbers refer to the version of code that would be in an eprom ecu. The number is always stamped on the factory eproms. Since your ecus are non eprom, you don't have to worry about it. As long as the number stamped on the white connector matches the old ecu, you should be good.
 
Don't worry about the E742 or E743 numbers. Those numbers refer to the version of code that would be in an eprom ecu. The number is always stamped on the factory eproms. Since your ecus are non eprom, you don't have to worry about it. As long as the number stamped on the white connector matches the old ecu, you should be good.

Good deal! Thanks for the confirmation!!!

Today I get home and get the other ecm repaired and test it. I also have new throttle body seals that just came in to fix my last and worste boost leak. Then I'll reset timing, idle and fuel pressure. Then get it out for a drive and do some logging to see how everything looks.

Thanks again everyone! I post up when its all done with the results.

Throttle body seals are in and done and computer number 2 is done. I'll get home tomorrow and try ecm number two and set idle, fuel and timing and then give it a test drive and see how it goes. if it goes well I use computer number two. if not I'll try computer number one and test drive it and hope one of the two computers or both are ok now. Fingers crossed. If then I'll be ready for the dyno saturday! :)
 
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Don't worry about the E742 or E743 numbers. Those numbers refer to the version of code that would be in an eprom ecu.

Correct. Those of are software versions numbers for the EPROM versions of that ECU. The ones listed are those that I've seen. Perhaps someday I'll make a "What do all these numbers mean" section for the list.

The most important number as you point out is the one printed on the white edge connector since many boards have been stuffed into non-matching cases over the years.

The number on the white edge connector should match the last four digits of the E2T number shown for each part number.
 
Cool thanks!

Pardon any typing errors as I'm highly frustrated at this moment.

This is what currently is going on with the car: Sorry I copied and posted it from a local forum.

Well, took a half day today. Got home and put the intercooler pipe back on to the throttle body elbow. Adjusted the idle which fluxes between 718 to 781 but, stays on 750 most of the time. I then set the fuel pressure and moved onto the timing. Of course I filled it back with coolant from doing the throttle shaft seals. The gas peddle feels better as well. I gave it some good revs into the boost and saw the a/f drop to the 11's as well real fast for a breif moment.
According to the logger the maf is reading the out side temp with in one degree and all reading look to be ok. This is also using the repaired ecm I got from brian. The origional looked a bit worse off so I'll save it as a back up if something were to happen. But, it seemed alright the other night. But OMG the thing sounds and revs so much nicer and sounds nicer as well. Fingers crossed still! I'm going to let it cool and top off the coolant and then take it for a test drive. This is were those crossed finger could make a difference.

Oh the isc seems happier as well I know they are to make some clicking noises but it makes a lot less now and they sound healthier as well. So I'm guessing its with it its range now and can do a better job. God I pray this all works!

Ok normal driving everything is ok. But it won't richen up under boost! I'm not sure if the fuel pressure is rising as it should or not. So I pulled over to check things out. To ensure its not the purge seliond before the afpr I went ahead and connected the lint from the intake mani right to the afpr. Going to go drive it again and see. Otherwise I think all is well but fuel trims are all at 100% and fto is about 118%. I don't recall that being right. Can anyone confirm? Any other ideas about it leaning out under boost would be great. Thanks!

Alright. Well, I saw no difference when swapping the vacuum line right to the afpr and intake mani. It might have been better but, not really worth mentioning as it was nothing consistant.

As well the fue trims from , low, medium, high and over all are all at 100% trying to add fuel still. Is this normal for say a relearn? I figured it might be some what but, it would right it's self pretty quick.

I also tried the origional ecm and I got the same results if not a bit worse. It would start off idling at a 14.7 but, then work it's way down to 18ish based on the wideband.

But, both computer dont do much in the way of richening up under acceleration.

At least the ecm I got from biran would hold a nice a/f at idle and driving but, wouldnt richen up either. Frustating.

Any advice?

I also checked to see if i had any service codes and nothing on both ecm's. This sucks!!!

Either both computers are bad still or there is something else wrong here. Could seriously something gone wrong during the boost leak test? I mean I heard the car hickup right after we started it from the blt but, then it seemed normal after that but, as soon as I started driving it home I noticed the a/f being lean and not richening up under boost or acceleration.
-----------------------------------------------------------------------------
in the logger it never moved from 2.96v. I'll see about getting this log up. I also at the end held it at 3k for a bit. I gave it some boost etc as well a bit at least twice. Traffic sucks!

ok, I also gave the exhaust manifold a visual inspection as well as the dp and I dont see any obvious leaks. Granted it was visual since everything was hot as f%$k!

I'm also giving the idea of trying to think were the o2 harnes runs. Is it part of the harnes that goes over and bolts to the intake manifold? I know for the BLT we removed those bolts and pull it back enough to get to those two vacuum lines under it. I wonder if something didnt short?

Is there a way to test the o2 sensor with an ohm meter and if so what do I set the meter to to check? It's a brand new sensor and has a bit over 2k miles on it.



http://www.plastikhosting.net/uploads/JRSTANGE/040811data/2011-04-08_14_50_31.csv

and the other version of it.

http://www.plastikhosting.net/uploads/JRSTANGE/040811data/2011-04-08_14_50_31.pdb

Going down to see if it's cool enough to touch and check out the harnes going over the intake manifold.
 
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