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ECU capacitor problems

Old 05-30-17, 04:40 PM
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Default ECU capacitor problems

I want to buy a 1st gen LS. What year marks the beginning of the end of the capacitor issue? When did Lex start using caps that didn't fail?


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Old 05-30-17, 04:44 PM
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Not the 1st generations. The 1st generations are now all pretty much project cars, old stuff needs fixing and parts replacing. So if you are looking for a project?
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Old 05-30-17, 07:08 PM
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to answer the OP's question, all 1st gens are susceptible to the capacitor problem. also some second gens, more so 95-97 model years. I have a 97 and have not replaced my ECU but there are others who needed to. as the cars got newer, there were less and less incidents of bad capacitors. to be in the clear you will need to go with a 2nd gen which has the least amount of ECU capacitor problems.
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Old 05-30-17, 08:47 PM
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All generations use QAS capacitors except very early ones manufactured in 1989 to early 1990. Toyota didn't use QAS capacitors at the beginning but they had different problems especially in very cold places and switched to QAS capacitors.

There are factors that affect the lifespan of those capacitors such as the ripple current, the temperature and the batch of capacitors. The last generation (VVT engine generation) has less opportunity to have problems due to the less ripple current. As far as I know, the early 2nd generation cars prone to fail faster than others probably because of the higher ripple current. I find some AT shifting problems among the last generation time to time these days.
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