Im lost....not ECU related???

[AquariumPerson]

Ok, so I have a 1990 Mitsubishi Eclipse 2.0l FWD.

Here is the deal, about 8 months ago, I noticed the notorious clicking/running problems associated with the ECU. So my dad replaced the cap's in the ECU for me, he did observe polarity. And the cap's were leaking, quite bad actually. Now, I put it in, and I STILL had problems and clicking,

the car set and ran only a few times these past 8 months, and finally I got a new ECU off of ebay, (well used actually). Same model number as my old one. I opened it up to look inside, did'nt appear to be tampered with. I did'nt really see any cap leackage, EXCEPT for a tiny few little "droplet" looking things on the big cap near the part that "plugs in". Well, I put a kleenex down there and swooshed it around and noticed I got up some yellowish fluid.


I put the ECU in. I drove a little bit, like 2 mins, in one direction down a road, then came back. Ran fine. Only drove for like 5 mins. But then my dad told me to drive longer than that, ok. So 1 min. into driving, AHH, no clicking, but I had problems, like the rpm dial thing went all the way down near the bottom, and it had NO power. Barely ran. So I managed to turn around and killed the car doing it, goins so slow in first. Well, the ride home, wasnt too good. Again, very little power and the RPM gauge WAS NOT working properly. When I got home I parked it, turned it off, re started it and it ran fine. Seemed to run fine, that is. And the RPM guage worked fine. NO clicking really, just when i turned the key to the off position there was one "click".


I don't get it?? I really need this car to work, that ECU I just got cost me $70, and they arent availabe on ebay too often. I'm starting to think the problem is not ECU related.

What do you think??


Thanks much, Adam

 

[92awddsm]

The tach issues are the #1 sign that either the power transistor is failing or not plugged in completely. This will also cause lack of powerr and running issues. Try removing the plug and reinstalling it. The transistor is located on the back of the intake manifold just below the plug for the coil pack. Make sure the connection is also good on the coilpack itself. This is all under the assumption that your n/t is a 2.0 and not a 1.8.

And the single click you hear after the car has been turned off is normal so no concerns there.

 

[AquariumPerson]

ok thanks I shall check that out....and report back

 

[AquariumPerson]

it IS a 2.0l btw..........

Can someone post a pic of the power transistor please?


Also, could either of the battery terminals touching the hood cause any problem???

And the rpm needle doesnt not work at all, it just displays really low rpms, unusually low, and then sometimes if I rev it up in neutral it will display like, 1000 rpms when i know its more like 3000.

And if its doing that above there are also power issues during that time, I don't know these days it just seems to have soooooooooo many problems

 

[AquariumPerson]

and the coil pack I guess, im not 100% sure what it really is, altho I think i know...

 

[92awddsm]

and the coil pack I guess, im not 100% sure what it really is, altho I think i know...

The coil pack is located on the driver side in the curved part of the intake manifold. It is the part that the plug wires connect to. There should be a 4 prong connector(3 prong on 91 and up) on the wiring coming fron the coils. Right below that connection, there is a thin flat sensor of sorts bolted to a bracket that is mounted to the intake manifold, You will also see a connector going to it that is about 6-7 wires all in a flat line. This is the power transistor. Let me see if I can dig up a pic. But yes, this will cause tach failure and power loss.

 

[92awddsm]

The best pic I can find at the moment can be found here: http://www.plymouthlaser.com/ttool.htm

It is in the 5th pic down right behind the tensioner tool. The white arrow on the far right almost points in the direction of the transistor. Unfortunately, there is no wiring hooked to it in this picture but hopefully it helps. I dont have my car or camera here at the moment so I cant snap a pic for you. I will try to get one tomorrow if you dont find it.

 

[AquariumPerson]

ok i found it. IT seemed to be slightly loose, dunno, came off easy. Well i checked it out and it seem'd fine and i plugged it back in, shaped like this right: I:- i know thats vauge but starts out flat then sorta dwindles down to a wire thing

umm hmm, im still going to have to drive it to see if it still does the same thing.

if any one has comments please post. thanks

 

[lasertim]

Also, could either of the battery terminals touching the hood cause any problem???

That can and will cause a lot of problems. A good friend roasted his ECU and then did the same to mine when I let him borrow it. It wasnt until I noticed a nice little notch in the hood bracing that we realized what was going on.

Why, is your touching?

And FYI, there are many different ECUs that will work for your car. See this link. http://simon.chi.il.us/ECU/ECUID.html

 

[AquariumPerson]

Will a big peice of rubber over the whole battery solve that? Because i have peices of pond liner that I could throw over it, just incase, then drive it and if the problem persists I know that's not it.

 

[95TalonOwner]

Will a big peice of rubber over the whole battery solve that? Because i have peices of pond liner that I could throw over it, just incase, then drive it and if the problem persists I know that's not it.

Yes that should work, anything to keep it from arching.

And FYI, there are many different ECUs that will work for your car. See this link. http://simon.chi.il.us/ECU/ECUID.html

He has a 1990 so he would need an ECU that was from 1990 dsm's only since 91 and up have some things changed in them.

 

[AquariumPerson]

OK, I cut a nice big peice of rubber, put it securely over the whole battery, and made sure the power transistor plug was plugged in nice and good. Drove a lot around the country, windows down, oldschool rap up, u know how that is.

Ahh the wonders of the DSM on country roads with the manual tranny, nothing like it.....

Anyhow, I really HOPE there is not gonna be any future issues. If there is it might be the coil pack, but I really do hope the problem was the battery terminals touching the hood. Well that rubber should have fixed that.

 

[AquariumPerson]

yeah about that ecu, mine is MD128624 and they don't seem too particularly common.......

 

[92awddsm]

yeah about that ecu, mine is MD128624 and they don't seem too particularly common.......

So, was the battery terminal actually touching the hood? Generally they dont touch on a 1g unless you have the wrong battery or have huge terminals/cable ends.

 

[AquariumPerson]

Might have, I don't really know. All I know is after I put the pond liner on top of the battery, I havent had any problem. I will probably drive around a little bit tomorrow and see If I run into any additional problems. It could also have been the power transister's plug in thing (not sure what its called) was loose. I made sure it was in there good. But if I know the ecu , power transistor, or the battery is not the problem, would it have to be the coil pack? I just want to make sure for the future.

 

[92awddsm]

Might have, I don't really know. All I know is after I put the pond liner on top of the battery, I havent had any problem. I will probably drive around a little bit tomorrow and see If I run into any additional problems. It could also have been the power transister's plug in thing (not sure what its called) was loose. I made sure it was in there good. But if I know the ecu , power transistor, or the battery is not the problem, would it have to be the coil pack? I just want to make sure for the future.

If the battery made contact with the hood, there would be some obvious visible signs on the bottom of the hood. If they were there, you would know and there would be no question about what they were from.

If it does the same thing, it could be the coil, but the coil doesnt make the tach fail like what you were talking about. The only thing that could affect the tach is either 1) the tack driver mounted on the 90 coil bracket, 2) the power transistor, 3) the tack itself, or 4) the ecu.

If your battery was grounding out, you would have most of the idiot lights come on on the dash, blown fuses, and fried ecu's. If none of that occured, its not a battery issue.

 

[AquariumPerson]

Well I did notice my radio and the overhead lights were not working the other day, and as it turned out a fuse WAS blown. So I replaced it, and its good now. Also when I was taking my old ECU out it touched the frame of the car and I noticed some quite large sparks, (I had the key to where the radio could come on for example, but not enough to start the car) the sparks like, came off of the bottom of the ECU so I could have fried that one..well the one I got off of ebay appears perfect and thats what I'm running now. ANd I did drive the car around a bit today to various places and it ran, performed fine. '

Ohh and I noticed the problems with the car running before, and AFTER I put the new ECU in. I really think it was either the battery or the power transister not being plugged in correctly. That fuse could have been blown by the battey touching, or was it due to the "sparks" off of the ecu when I was removing it? (should have taken the key out)