tpnotch420

I have a 92 sc400 with 179K miles I just had my engine replaced everything seem to be going fine until my mechanic told me that the idle was off and suggested I replace the wires. So he did and after doing so now it won't start at all. You turn the key and it sounds like it wants to start but nothing happens. So after checking the crank sensors he thinks it's the igniter modules. So I picked up 2 modules from a salvage yard we tried those still the same thing. I'm wondering is there any way to test the modules to see if they are working? It seems odd that I would have encountered 4 bad modules. If it's not the modules his next guess is the ecu. Is there anyway to test the ecu? does anyone have any other ideas of what might be wrong?
Thanks for any help you can give.

jibbby

Get a new mechanic and get your money back!!!!...If the idle was just off, and now he can't get it running and says you need this and that and then maybe a new ECU, then I would say he is an idoit, and should learn his trade better...

You need to see if the fuel is being delivered, then if the ignition is firing, if both are then go from there...Man, I hate stupid mechanic's....Good luck...

Is the engine that was replaced matched for the same year? Wiring harnesses all matched up correctly? Is the MAF and sensors all in order, TPS sensor intact, etc.. etc..

tpnotch420

he says the harness matched up fine and that he's tested all the sensors and they are all working the car turns over but no spark. The guy seemed pretty intelligent but I don't think he's had any experience with a Lexus. I'll take the blame for not doing a better job of qualifying before hand. But now I just want to get the car running again

sc250tt

sukks man . i have a 92 computer if u need one

mkorsu

This sounds simple but have your mechanic check the 2 coil packs. Common for them to go and the "no spark" issue is indicitive of this.

tpnotch420

I will double check with him to ensure he has checked the coils

tpnotch420

okay so he says the coils are fine. Any other ideas? is there a way to check the igniters and the ecu to see if they are the problem. I'd hate to replace them if there is nothing wrong and I know I can't take them back once I open the box.

jibbby

Was the ECU working fine right before the swap? It should not have gone bad just because you swapped in a matching engine.....Unless, some wiring shorted out occurred, because of non-matching wires or mechanic's error...Atleast you now know where the problem is, and that is a good thing.. Ignition can be tested, problems can be found by any decent mechanic with the proper tools and knowledge...Does your mechanic even know where the ECU is? I would try unplugging everything including the ECU, wireharness, etc, reset and plug it all back together again and see what happens.....It sounds to me like there is some wiring trouble somewhere...Good luck man...The ECU is encased in a little silver box that is located on the passenger side seating area where your feet would be. Lift the upper carpet and the ECU is hiding behind a couple of screws..The ECU can be unplugged, I would inspect all the wiring again, I dought the ECU just fried out...