1991 ecu substitution 50042 vs 50020
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1991 ecu substitution 50042 vs 50020
My car is exhibiting ecu wonkiness, i.e idle problems, random stalls etc. Dealer wants $1600 to replace it with a rebuild (the new part is $2000!) and I'm not going to spend that kind of money on a 23 year old car. I've located a replacement ecu cheaply but it's the 50042 version not the 50020. I've seen posts that intimate that the 50042 was the universal replacement for the 50020 and wondered if there would be a problem in substituting an ecu which was specified for a traction control car in one without traction control?
#2
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the replacement will quickly have the same problems, why not fix it yourself for a tiny fraction of that cost using my tutorial on fixing your failing ECU capacitors
and yes, swapping ECU's with different part numbers is never a good plan (save for the substitution where there just is a minor software upgrade and the part number varies by a single increment, like going from an 89661-50303 to an 89661-50304) and I would forget any ECU labeled as "rebuilt" or "refurbished" other than those at the dealership - the rebuilders on ebay and elsewhere on the Internet seem to have no clue that these ECU's require a very special and rare type of capacitor that is simultaneously low-ESR, high temperature, long life, and has high ripple current rejection - a type that is only available from just 4 companies in the world, all Japanese. - They are very hard to find and much more expensive so the rebuilders just use whatever cheap crap capacitor they can find and the problem is not solved, and may even become worse!
and yes, swapping ECU's with different part numbers is never a good plan (save for the substitution where there just is a minor software upgrade and the part number varies by a single increment, like going from an 89661-50303 to an 89661-50304) and I would forget any ECU labeled as "rebuilt" or "refurbished" other than those at the dealership - the rebuilders on ebay and elsewhere on the Internet seem to have no clue that these ECU's require a very special and rare type of capacitor that is simultaneously low-ESR, high temperature, long life, and has high ripple current rejection - a type that is only available from just 4 companies in the world, all Japanese. - They are very hard to find and much more expensive so the rebuilders just use whatever cheap crap capacitor they can find and the problem is not solved, and may even become worse!
Last edited by LScowboyLS; 10-13-13 at 08:14 AM.
#3
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Well I opened up the dash and retrieved my old ECU which was a 50032 not a 50020 as I thought and plugged in a 50042 unit and all seems well so far. The last 2 days it's worked ok so I have to give it some time and miles to see if the problem is fixed with the "new" ECU. I am going to open up my old unit and look at the condition of the capacitors; pix to follow if there is something to see.
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