Ls400 Intermitently Cranks But Wouldn't Start

[mariusp66]

Hello,

I have this weird problem with 1992 LS400.

Car starts fine every time in the morning or whenever it was stopped for longer periods (few hours). But sometimes, after driving a while for it to warm up to normal level, if stopped and attempted to start it again right away (in a minute or so) car would crank but engine wouldn't start. However, after waiting few minutes (4-5 minutes) it will start again just fine as always. Feels like something inside has to cool down to start again. Battery is fine, starter is fine, temperature gauge on dashboard never comes above the middle. This phenomenon however does not appear consistently because I am testing it now and then. For instance, I would park at the office parking lot when arriving in the morning, stop a car and then try to start it again. One day it would start just fine and the other would not. I leave it there, come back to drive for lunch and starts just fine as always.

I realize this could be caused by hundreds of problems but wondering perhaps somebody is or were experiencing something similar and would share it with me.

Thanks,

/M.

[Alexander the o.k.]

Have you pulled the engines codes?

http://www.lexls.com/tutorials/intro/codereading.html

It's easier than you might think. Try it.

[Imzjustplayin]

Hello,

I have this weird problem with 1992 LS400.

Car starts fine every time in the morning or whenever it was stopped for longer periods (few hours). But sometimes, after driving a while for it to warm up to normal level, if stopped and attempted to start it again right away (in a minute or so) car would crank but engine wouldn't start. However, after waiting few minutes (4-5 minutes) it will start again just fine as always. Feels like something inside has to cool down to start again. Battery is fine, starter is fine, temperature gauge on dashboard never comes above the middle. This phenomenon however does not appear consistently because I am testing it now and then. For instance, I would park at the office parking lot when arriving in the morning, stop a car and then try to start it again. One day it would start just fine and the other would not. I leave it there, come back to drive for lunch and starts just fine as always.

I realize this could be caused by hundreds of problems but wondering perhaps somebody is or were experiencing something similar and would share it with me.

Thanks,

/M.

Fuel injectors, fuel pump, fuel filter, sparkplugs, coils? I don't know but those are my guesses, otherwise if you still don't see codes you could have a weak battery. This does seem like an odd problem as most issues are with cold startup and not when the car is warm.

[vyhanh]

Hi,

My son's 91 LS400 never has the problem but my 92 Honda Prelude does (regularly). The cause is one of the (MAIN) relays.

By the way, this only happens when the outside weather is hot and humid

[mariusp66]

Hi,

My son's 91 LS400 never has the problem but my 92 Honda Prelude does (regularly). The cause is one of the (MAIN) relays.

By the way, this only happens when the outside weather is hot and humid

That was my guess too. I had that problem with MAIN relay and relay box, however when there was problem with main relay it was even stalling while driving and then wouldn't start too. Now it never stalls but can't start from time to time while warm.

/M.