Henry754

Hello fellow members, I am the proud owner of a 1994 ls 400 which has about 140k miles on it. It has recently been stalling and eventually cutting off completely after driving it for about 30 minutes. I noticed that when it cuts off, the longer I wait before cranking it up again, the longer it will drive before it eventually cuts off again. The weird thing is, when it cuts off and I leave the key ignition turned to where there is power to the radio, it will not crank at all; but when I take the key completely out and wait several minutes, it will turn on. Can someone please help me!

timmy0tool

iTrader: (7)

sounds like a heat related issue. as the car warms up the problems worsen. what i would guess is that the capacitors in your ECU have been compromised.

detailed thread here:
https://www.clublexus.com/forums/ls4...capacitor.html

PerpLexusd

something similar happened to me and it ended up being the crank position sensor

steve2006

I'd be thinking CPS also, get some freezer spray and the next time it does it spray the CPS with it and then see if starts right up.If it does replace it.

LScowboyLS

also try the freezer spray in places such as the relay box, and on other electronic components

you don't happen to have one of those infrared laser thermometers or an infrared camera do ya?

Henry754

Thanks for your reply. So I had the computer looked at by an electrician and we discovered that the capacitors were not leaking. What do you think could be the issue since my vehicle is exhibiting those symotoms you listed?

timmy0tool

iTrader: (7)

remember capacitors do not necessarily have to physically be leaking to be compromised.

your problem sounds like a fuel pump relay issue common on hondas due to cold solder joints. i know this is a lexus but i would check fuel next. do you have any check engine lights? are your battery terminals tight?

fixmiester

I have to read between the lines here, but I think you said : the car DIES after running awhile. Then, if I leave the ignition switch ON for awhile, it will not even crank. If I turn the ignition switch off for several minutes, it will start and run for awhile. Is that what you mean? If so, you have a bad alternator, and the battery is draining itself dead. It does recuperate after awhile with no load; the longer the better, and it usually will start up again, until it again goes dead from not being charged. Check the voltages on the battery before starting, while running, and running under load. Let us know what you find.