Toasted ECU?

[UnluckyGSX]

Hi I'm kinda new, but I've been lurking around for about a month and a half.

Well tonight I was driving to my girlfriends house when my car just up and died. No sputtering, no popping, no explosions.. however the inside of the car smelled strongly of electrical fire. I've gone over everything and I can't see anything wrong on the surface. Since we only smelled it inside the car and not under the hood I'm thinking it's the ECU and from other posts I've read that seems to fit. I just kinda want to get a second opinion. Any help you can give is greatly appreciated.

 

[mitsutuner]

Sorry if I sound like the grim reaper, that's not something I'm proud of. I'm only trying to shed some light on the truth based on my experience & that is that you can never underestimate a mitsu's capacity for failure.
Having said that, your car is probably safe to drive despite all the potential maladies I've listed previously- just keep in mind what tommorrow might bring.
It's not the end of the world when you own a crappy car, but go ahead & shoot me if you see me on the street anywhere near the mitsu dealer.
Above all, an enormous sense of humor will carry you thru most mitsu disasters & might stop you from going postal. keep smiling!

 

[GTM]

Originally posted by mitsutuner
Sorry if I sound like the grim reaper, that's not something I'm proud of. I'm only trying to shed some light on the truth based on my experience & that is that you can never underestimate a mitsu's capacity for failure.
...
Above all, an enormous sense of humor will carry you thru most mitsu disasters & might stop you from going postal. keep smiling!

Nope, you were pointing out what in the overall scope of things is too much a reality for a lot of people. It's a hairy beast that gives no quarter, which to meet smog laws has had to suffer the fine line of adding too much to control while giving the customer creature comforts of a grand touring car. On top of that you have different design teams perhaps in different countries having to make compromises to the other. Knowing this may not help when trying to maintain your sanity when all you want is 1 week peace of mind.

Cheers,
GTM

 

[mitsutuner]

yeah, 1 week is a long time in mitsu world. I'm so paranoid that I don't play music in the car for fear I won't hear the early warning signs of the next failure that's going to leave ne stranded. I wouldn't consider taking the car more than 100 miles from home, my blood pressure elevates just driving it around town. I always take 3 deep breaths before I start it
My honey hates that car, I spend way too much time in the garage & she knows I'm not approachable when I'm wrenching on it.. I had the car 3 days when the alt. failed leaving me stranded at the front of a long line of cars at a busy intersection. Honey had to steer while I pushed the car thru the intersection & then she slammed the car into the back of a parked van because of no power brakes!
I can laugh about these things now, but I'll be crying when I get the bill for the ECU.

 

[UnluckyGSX]

So do you think my alternator could have caused the ECU to explode? Also what was that thing you were talking about leaking on the powersteering pump because my PS pump just started leaking and it would be nice if I could fix it without replacing it (PS fluid leaking onto my alternator can't be good).

 

[mitsutuner]

DOH! What cooks your ECU is a combination of recuring events that produce heat. Your arcing B+ wire caused a voltage surge with every arc that is felt by the capacitors in your ECU. The job of the caps is to dampen these surges so they don't damege your ECU micro-chips. But the caps have a limted life by design & these surges produce heat in the caps which contributes toward their premature demise. the electrolyte inside the caps melts & leaks out the bottom of the cap cannister thru the rubber seal and etch & burn the board & components on the board nearby the caps.
Other sources of heat add to the problem, locating the ECU near the heater box & the fact that the ECU has neither heat sinking mounts nor cooling fan, as does your home PC CPU. (WHY OH WHY MITSU?)
An ECU visual inspection with a lens will tell you if the caps or board are damaged. especially in light of knowing the inherent stresses already present that cause a high failure rate as witnessed by every dsm forum on the web of which there are many. It's pretty quick & easy to pull the ecu out & look at it.
The big idea is to catch ECU failure asap because, once the micro-chips require replacement, your ECU has no core value & you'll end up paying almost double for your replacement ECU,($425 versus $225 in my case).
Plus, the mitsu ECU has a way of knowing when is the least convenient time for you to be stranded with a non-running automobile, 100% of the time- it's the most reliable feature of the car & this cannot be overemphasized.
In my car, the PS fluid was leaking out from under the nuthead on the big bolt that mounts the hose fitting to the pump & you might get away with just tightening it, but if you remove the nut you'll wonder why mitsu didn't put a 2 cent washer under the nut--it's that obvious & that easy to fix!!! No rocket science here!
No, you won't have to drain the fluid, or seperate the fitting from the pump, just pack a rag around it & cover the alternater below with a small piece of cardboard or plastic bag--there will be a very small amount of spillage, You might have to replenish a few drops after.
It's the leaking fluid dripping down into the alternater & alternater wires & connectors that's going to cause problems at some point & might be part of what ate your B+ wire insulation.

 

[UnluckyGSX]

So what is this B+ wire and what does it go to?

 

[GTM]

Originally posted by UnluckyGSX
So what is this B+ wire and what does it go to?

mitsutuner has mixed up some of what happened to my son's car and yours.

The B+ is the large wire out of the Alt. that goes to the battery for charging. It is hot all the time, in other words not switched thus a short could spell serious disaster to the loom.

If you have access to Stodard(sp) solvent or some kerosene you can try to wash some of the oil out of the Alt. Make some sort of baffel to keep the oil from the P/S pump leak from dripping on the Alt.

The oil and resultant grung that collects cuts down on air circulation and heat builds up, burns through the insulation... poof there's another $100 gone.

Cheers,
GTM

 

[UnluckyGSX]

Ahh.. was just curious because my ECU didn't show any of the usual symptoms before it went.. just kind burst into flame with no warning.. no ticking, no smell.. so I kinda suspect that there may be something else wrong in the wiring that caused it to go into meltdown

 

[GTM]

Originally posted by UnluckyGSX
Ahh.. was just curious because my ECU didn't show any of the usual symptoms before it went.. just kind burst into flame with no warning.. no ticking, no smell.. so I kinda suspect that there may be something else wrong in the wiring that caused it to go into meltdown

From what you have given, I've no reason to suspect anything specifically caused the problem. Depending on how much oil is inside the Alt. it could be a possibility the brushes were arcing thus causing surges / spikes.

A pet peeve of sorts is not giving the the charging system a chance to replace what was just taken out in starting before switching everything on and driving off. I've got no rule of thumb here but a gut feeling that 6x the number of seconds of cranking to start would replace the withdrawal. This is going to cure anything, it can give the electrical system a bit better chance to stabalize without trying to run all the draw and charge the battery.

Making any progress on finding an ECU?

Cheers,
GTM

 

[UnluckyGSX]

Yeah actually, hopefully I'll be buying a EPROM ECU with the caps already replaced for $200. I just gotta get pay-pal to confirm my bank account and hope he doesn't sell it to someone else.