I'm currently driving a 92 Lexus LS400. Today I had an odd problem. I had driven about 45 miles with a couple quick stops interspersed when the car started losing power, not revving, and eventually stalling. I pulled over, cursed the car gods and my luck, and cranked it over. To my surprise it fired right up and acted like nothing was wrong.
I got going again just fine but about a mile down the road the same thing happened. I pulled over again and this time let the car sit for 15 minutes or so. I should probably note that the temperature gauge read perfectly normal, no idiot lights were on, and everything seemed peachy even as this was happening. Fired it up again and was able to continue the 12 miles back home like nothing was wrong.
Things to note:
It was stupid hot today, like 95 degrees and sunny.
I recently recharged the AC and today was the first time i've really used it.
There's nothing I hate more than intermittent problems, anyone have any ideas?
thanks!
Has the fuel filter been changed recently?
Not sure, just bought the car in February. That was what came to my mind first too.
Fuel filter is the place I'd start.
Extra info: Since ive had it, its always hesitated a bit when you first get on the gas unless you really ease into it. Fuel filter looks stupid simple to change on these, ill probably start there.
Can you check for codes? Our 99 has gone into limp home mode a couple times, but it's throttle by wire. The last time, I rebooted that computer (VSC) and noted that the throttle cable was loose. Tightening up the throttle cable seems to have solved that problem.
On a related note, I just finished changing the timing belt. I'm now at the point that I kinda don't like timing belts. This one took about 4 days, maybe 15-16 hours total work plus extra runs to the store. Every accessory had to come off or loose: PS pump to get the alternator off, AC compressor, idler pulleys, etc. I didn't add up all the parts, but I bet I'm pushing five bills, counting the spark plugs, coolant, air filter, serpentine belt, hoses, etc. On the plus side, I'll have to admit that working on a LS400 is really not that bad. The BGB (Big Grey Book) is very well written and shows you most of the "gotcha's."
If you cover the basics and still have the same problem, pop open the ECU to see if there are any leaking capacitors. It's not rare for early LS400s to have ECU problems, the company that supplied them had subpar capacitors- stolen design that turned out to be unstable years later.
Well, shoot! I guess it had to have trouble eventually. I don't believe that I ever changed the fuel filter, and we had it for 4+ years. So that's not a bad place to start. We never experienced those symptoms though a couple times it did stumble and idle too low after having had the battery disconnected for a while, during the ECU's re-learning process. [first time was for major tune-up, second time for alternator replacement.] But both times that happened, it cleared up within a few minutes of driving.
I also hate intermittent problems. I'm still battling one on the Volvo 850 that had me questioning whether I sold the wrong car. It just doesn't want to start some days. I believe I've traced it to the camshaft sensor connector and just haven't taken the time to replace it.
Good luck!
lnlds
New Reader
5/29/12 1:45 p.m.
Coolant Temperature sensor? When I had intermittent stalling issues with my 94 celica, which turned out to be distributor related, the internet seemed to agree that coolant temperature sensors are likely suspects for intermittent stalling issues with early 90s toyotas.
The hesitating unless you ease into the gas reeks of the Intake Air Temp sensor assuming you don't have a timing or fuel delivery issue.
I bet if you shifted it manually and romped on the gas after you gently got it up to about 3500rpms, it wouldn't hesitate at all.
I can see a MAF/MAP sensor or crank position sensor causing similar problems. Both susceptible to heat failure.
Gonna start with the fuel filter, its cheap. Drove another 10 miles or so today no problem.
That jogged my memory; if you have the problem again make sure to check the fuel pump relay socket. When I got the car (non-running) one of the problems was the fuel pump relay socket. Someone had sprayed a bunch of white silicone lube in there (??!!) so I knew there was something up. I cleaned the silicone out and the fuel pump still didn't want to run. I tightened all the sockets (using a small flatblade screw driver) and then it worked great for the rest of the time I owned it. So it might be worth double checking those sockets.
Well the fuel filter appears to be OEM or darn near it. Being in Ohio that should make things fun. Have it soaking in PB blaster for now. Pushing 200 miles and still no repeat, it's also been much cooler outside lately. If it does it again I'll check the relay socket, thanks for the heads up.
Does the exhaust note change noticeably? I had a really inconsistent power loss on my miata, high load, low load, cruising, seemingly at will. Turned out to be a chunk of catalyst had broken out at the rear of the cat, and sometimes it would turn sideways while resting against the outlet and block almost all flow.
so heat seems to be the outside action causing the issue..
Coil over heating ? Or some other ignition component.
Coil failures can cause weird driveability problems on those cars, They only run one bank so it can still run but basically half the engine isn't doing much
