I have a 93 Lexus SC400 that has been in the shop for almost a year. I never had any problems with the car and it just stopped running. I thought was the ECU so I sent that to Fla. in which they said they had to rebuild the ECU about $400.00. I get the ECU back and it sounds strong but never turns over. I had it towed to a shop here in Columbus, Ga., that specialize in foreign autos and they said the same thing and sends the ECU back, still nothing. Techs think it has something to do with the security system, but can't figure it out. 11 months later still nothing. I don't know what to do at this point. We don't have a Lexus dealer here. I loved that car, but know I'll never buy another Lexus. This is insane, a year still no progress. Can anyone give me serious advice on what to do?

 

Well sounds like bad fuel pump computer . Did you had them check if you have spark on all sparkplugs did you have them check if you have fuel at injectors.

 

when the main ecu goes bad it usually runs, just very badly. when it stops running and will try and start but not turn over, its usually the fuel pump ecu that is the problem, it is very common on these cars most people replace or bypas it at some point.
Wish you had come on here earlier because we would have told you that is the problem and you can do the 12v fuel mod and be back on the road in like 30 minutes.

https://www.clublexus.com/forums/per...tures-faq.html

 

I cannot choose any of the options listed. You need to add the option, "Learn yourself and DIY" As Ali mentioned, try the fuel pump ECU 12v mod out. Listen for the fuel pump running. GL.