Just purchased my first lexus. Its a 92 ls 400 with 108,000 miles I only paid 900.00 for the car and it is in great shape. I bought it from a guy that was stumped on why it wouldnt start. The fuel pump he replaced along with the coil pack,and distibutor caps. The car is getting spark to the plugs and there also wet with gas, so its also getting gas. I am a newby to the lexus scene and I want to get this car runnin. I could use some help on common problems with why car will not start. Also the engine is cranking over. Could it be mass air flow scensor or ? Please help.

 

Spark, Fuel, Compression. Does it cranks over normally? Or slow? Or makes weird noise? Spark is the easiest to check. But as for fuel, how do you know you have fuel? Lastly, would be compression.

 

when all else fails, start over...

check for fuel

check for spark

are we doubly sure these are both happening on all 8 cylinders???

 

just a thought, but my friend recently had his 91 LS400 just die while driving. Would crank but not start. My other friend who is more mechanically inclined found out that the problem was with the Timing belt tensioner. Not the drivebelt tension but the one for the timing belt.
They changed it and the car started right up. Once you see it you'll know if it's bad. While you are there might as well change the timing belt too! Hope this helps.
Also, if it would start you would have to floor it just to get it to idle. Then the idle would be all rough an you could never get the rpms up.
I guess my friend checked the compression and was able to figure this out since half of the cylinders had low compression!

 

Yea if the car cranks and makes a weird, nasty, crying noise however you describe it... Your losing compression because the timing belt is broke!

 

most likely it in the timing belt because if it has spark then its not the coils or the ecu once you jump timing that it, it will never run and if it did it would be really quick the other is it will make a very fast cranking sound like one you have never heard if it is the timing belt because the only thing that would be turning is the crank nothing else.

 

I guess I need to check compression thats something I havnt done yet. But the way its cranking over sounds normal to me acts like it wants to start. Has anyone ever had fuel pump relay go bad. I dont no when I checked plugs for spark they seemed wet with gas.Could smell gas. But who knows. Cant find a repair manual anywhere.

 

I have a 93 with a similar problem. I took it toa Japanese Specialist garage, who I have used to replace timing belt, etc. in the past on this car. It is not getting spark or fuel, but spins over easily, no noise. Timing belt is fine, compression is fine. Sometimes it starts for days, then quits. Without doing anything, it may start within minutes, hours, or days, and be ok for days. Sometimes it won't start for days, then starts again. The car won't " Throw a Code ", so, this mechanic is stumped & so am I. Anyone HELP??