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Maybe i will look for a used ECU with the same number and try it, i
I agree with Bob (OhioSpyderman) ECU looks clean, but I will add that the radial capacitors look to be original and they can fail without any visual evidence. If they haven’t already failed, they will before long.

So when look for used ECU, might try to find one that capacitors have already been replaced.
 

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Thank you guys for all this information as my 93TT just started doing the same thing as the flyingeagle's car. I thought it was the fuel pump so I upgraded it and still had the problem. My battery is fairly new but we found that when we hooked it up to a battery charger it started every time. When we took it off it was intermittent starting. So we checked the ECU and replaced three of the capacitors hoping that would do it but I'm still having the problems of intermittent starting. Having read thru your posts it looks like there are some more things to look at! Thanks for sharing and hopefully both flyingeagle and myself will find our solution.
 

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Fairly new here had same thing happened it was the cam position sensor 6 months chancing the issue on and off got on eBay for like 30.00 working ever since. My 2 cents cheap enough to throw at it
 

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Hey Flyingeagle...I currently have 8 of these cars and am learning every day. I've had a couple of no-start conditions over the years and it's been a myriad of different things that were the culprits. The most recent one was this: Car would crank but not start. First thing I did was swap out the factory ECU (they are notorious for the blown capacitors....so figured it was relatively quick and easy to test) and since I have Qty 2 (known good) 92 TT ECU's on the shelf, I did a quick swap. Nope, still no start. Hmmm.... so I grabbed my Fluke Multi-meter and checked for power at the fuel pump (top of fuel tank...you access it in the trunk area by the spare tire).

I found I had no power at key on, and no power at crank. Now, keep in mind, on these cars (from what I recall) you won't get power to the fuel pump at Key-On....I think you only get power at the pump when you crank the engine and/or when the car is running if I recall correctly...which I thought was weird...but I digress. Anyway, no power at the fuel pump....hmmm...... so I swapped out the MFI relay (it's bolted to the passenger side of your center console...hidden just behind the carpet....kind of by the passenger's feet well area) Ok, changed that baby out.....still no start. Hmm..... Ok, so I cracked open my factory Mitsubishi service manual....(shit's getting real now folks) and traced the routing of the power from the battery to the ECU to the relay to the pump, etc... and it appears as though there is a relay under the hood (kind of under the factory air box) so I look and look, and SURE AS SHIT there it is! Mine had like a little rubber dust cover on it...well, I Iooked in there and dude, it was corroded badly from water intrusion!!! Found the part number, got a new one, and VROOOOOOOOOOOM, she fired to life!! So, that's one possibility.

Hope that helps someone out there.
Rick
 

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I found I had no power at key on, and no power at crank. Now, keep in mind, on these cars (from what I recall) you won't get power to the fuel pump at Key-On....I think you only get power at the pump when you crank the engine and/or when the car is running if I recall correctly...which I thought was weird...
FYI… It’s a safety issue that is meant to only allow pump to run when engine is starting or running. If engine fails for any reason the pump will stop within matter of seconds. Since they couldn’t do that if pump ran off ignition on position, they choice to use starter circuit to start fuel pump which then was maintained by ECU while receiving run signal from engine.

... and it appears as though there is a relay under the hood (kind of under the factory air box) so I look and look, and SURE AS SHIT there it is! Mine had like a little rubber dust cover on it...well, I Iooked in there and dude, it was corroded badly from water intrusion!!! Found the part number, got a new one, and VROOOOOOOOOOOM, she fired to life!! So, that's one possibility.
That is the low/high speed fuel pump relay that only TT engines have, NA engines only run pump in high off the MFI relay with smaller volume pump. So sounds like the relay legs/connector had enough corrosion not to allow any current flow thru either low or high speed circuit to pump, only difference is a resistor in low speed branch.
 

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Rather than the fuel pump hotwire, the fuel pump relay bypass was one of the first "mods" I did on both my cars.
Being located where they are, even enclosed in those rubber boots, they still collect water and eventually corrode, which makes the voltage drop worse over time.


Bob. :)

EDIT: I should probably add, even after doing the bypass, I put the boot back on and electrical tape the crappola out of it :)
 
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Check the crank position sensor. I had a crank no start condition years ago and went to the service manual where there is a sequence of things to check if there is cranking but no start. If that turns out to be the problem try Autozone; they sell the OEM Mitsubishi part in a repackaged "Duralast" box. Well, they used to do that about 7 years ago so maybe they still do.
 

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Discussion Starter #29
Hello guys, unbelievable response, THANK YOU.
Just to update my situation, i decided to send the ECU out to be refurbished, even if there is nothing wrong , i told them to replace all the capacitors that are known to have failed. I will update once i get it back. I have a picture of the relay beside the passenger seat and every time i was cranking i heard it click, i am assuming that it is working ok.
288816
 

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I have a picture of the relay beside the passenger seat and every time i was cranking i heard it click, i am assuming that it is working ok.
That’s the MFI relay, which should click once when key is turned to ON position (powering components) and click again as soon as switch is turned to start position (starting pump).

However, it should not click a second time while cranking which I’m not sure if that’s what you meant.
 

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Here's something I put together a while back, not sure if it will help

 

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Yes, replace the caps. I did the same thing, and it didn’t work.......I sent the ECU back and the guy found corrosion, fixed it, and he said he found a new way to :test: the circuit board.




Cars runs great,,,,,,,,just throwing it out there cause my check engine light did not come on after caps replacement, although tho the ECU was still at fault.....

But I will say it again, that car isn’t going anywhere unless you get the check engine light to come on before you start it
 
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