krezzo

Hello. I have a 1991 LS400 with 420,000 miles. A few weeks ago, after turning off the engine at a shopping center, I tried to restart the car and it would crank but not start. The battery is strong and was actually replaced in December. I had it towed to my mechanic and he said the computer module was kaput and he would send it out for a rebuild. The rebuild shop said that the computer module was too far gone for a rebuild and they sent it back to him. He then purchased a used computer module and installed it in my Lexus. I drove away from the mechanic's shop and the first time I had to turn off the engine (at a gas station) and tried to restart it, it would (again) crank but not start. I remembered reading in these forums that if I unhooked the negative terminal on the battery for a short time and then reattached it, the computer would reset. I did this and it did reset and the car started fine. Does anyone have any ideas of what might be going on with my Lexus? Could I have 2 bad computer modules in a row? Or could something be causing the computer module to go haywire as opposed to the module causing the problems? Thanks.

Kathy

pmarr

420,000. Impressive

jadu

iTrader: (42)

It is highly likely that both of those ECU's needed to be rebuilt. The first one that got sent out may have required too much rework. Do you know if the second ecu that you have now was rebuilt?

krezzo

I don't know if my new used ECU was rebuilt. I will find out tomorrow when I go back to the mechanic. My invoice indicates a 90 day warranty along with a $350 part cost. I was hoping that for the price, it had been rebuilt. I did take the opportunity to check and make sure my anti-theft system was not interfering in some way with the starting of the car, but the red light does extinguish when the key is inserted so I don't think the problem rests with that.

dicer

If truly the disconnect and reset did help then very likely an ECU related problem. But also crank and cam sensors can cause the no start problems as well.