BillyC

Can you tell me what the throttle position sensor looks like and where on the engine it is located? Thanks, BillyC

Hi All, My 1991 LS400 (238K miles) cranks over but will not fire below about 40 degrees, or if it does fire up it immediately dies as if out of gas. When this first happened the temperature was below freezing so I poured in 2 bottles of Heet thinking perhaps condensation in the fuel system had frozen. Later that day after the temperature had warmed up into the 50's my Lex started on the first turn as usual and ran fine for the several relatively warm days that followed. Then came a night of 38 degrees and the problem reappeared. Obviously not frozen condensation, but what? I am stumped. Can you tell me what could be sensitive to temperature? Thanks in advance. BillyC

Hi, Your mention of a problem "below 40 degrees" made me wonder if it could relate to my problem. My 1991 LS400 (238K miles) cranks over but will not fire below about 40 degrees, or if it does fire up it immediately dies as if out of gas. When this first happened the temperature was below freezing so I poured in 2 bottles of Heet thinking perhaps condensation in the fuel system had frozen. Later that day after the temperature had warmed up into the 50's my Lex started on the first turn as usual and ran fine for the several relatively warm days that followed. Then came a night of 38 degrees and the problem reappeared. Obviously not frozen condensation, but what? I am stumped. Can you tell me why your throttle position sensor was sensitive to temperature? Thanks for any help you and other members can provide. BillyC

On the way to work this morning, the traffic was moving at idle speed and then stopped. I had looked away for a moment and ran into the vehicle in front of me. That vehicle suffered minor damage to it's rear bumper, however, since it was an SUV the bumper rode over the top of the front bumper of my 91LS400 and did major damage (broken headlights, broken grille, buckled hood). I really like to drive this car, but now I am faced with the problem of having to put 2 to 3 thousand into repairing it (no collision insurance, just liability) or to do what with it? Have any of you faced this situation? What did you decide to do? TIA. BillyC N. Alabama

Thanks for the info Curt. If the ac high pressure switch is set for 455 psi on the R12 system as it is on your R134a system, then I guess I don't have to worry about 325 psi. Regards, BillyC 91LS400, 232K miles

Does anyone know at what AC high side pressure the condenser fans are set to turn on? My 91LS400 waits until the pressure is well over 300 psi before turning on. Once the fans are on, the pressure immediately drops to 250 psi where I'd like it to be. I am afraid that this excessively high pressure will blow a seal or pop a hose. TIA, BillyC 91LS400 232K miles North Alabama

I just searched on "fans" and read all the posts. There is some excellent information on check out of the condenser fans, but I did not see the pressure at which the high pressure switch turns the fans on. When refilling my AC system with R12, we discovered that my 91LS400 high side compressor pressure is reaching 300 - 325 psi before the fans turn on, after which the pressure immediately drops to 250 psi where it should be. I am concerned that these extremely high pressures may blow out a seal or rupture something and would like the fans to turn on sooner. What is the psi at which the high pressure switch is supposed to turn on the fans? Thanks in advance, BillyC

My radio is working again and I didn't do anything to it! I would think that we are dealing with a loose wire here except that it fixed itself while sitting still. Any ideas? BillyC 91LS400 238,000 Mi

One day the radio (Pioneer, I think) on my 1991 LS400 was working with no sign of a problem and the next day when I turned it on the volume had to be turned fully clockwise to hear just a low output from the speakers. The radio appears to be tuning the stations properly; I just don't have sufficient volume. Has anyone had a similar problem? Thanks, BillyC 91LS400 239,000 Miles

I agree with your assessment of the travelling comfort and reliability of the Gen I Lexus. I have driven mine from Huntsville, Alabama, to Corpus Christi, Texas, several times (round trip 2000 miles). I get 24-26 miles per gallon at interstate speed of around 75 miles per hour. Twelve hour drives are no problem with the comfort of this car. I assume that later model Lexus cars have maintained this comfort level, but I have no personal experience with them. Happy travelling. BillyC 91LS400 216K miles

My radio LCD is working fine - how about an OEM contact for the Temperature/Time display LCD? BillyC 91LS400 216K

SKPerformance, I had not heard of motorvac for unclogging the EGR. Is it some kind of suction device? Can you describe the procedure a little? Thanks, BillyC 91LS400 216K

My check engine light went off on the way home from getting the local Toyota dealer to read the code. Yippee! He said the EGR pipe was plugged, but I decided not to have the work done due to time constraints. My car is running great and getting the best gas mileage ever, 26 mpg. I don't plan to do anything about the EGR until the check engine light comes on again. Is the EGR just for emissions control or does it have some other function?? Thanks, BillyC 91LS400 216,000 miles

I had my check engine light diagnosed today at the local Toyota (not Lexus) Dealer. It cost $40.00 which can be applied to the bill if I take it back for repair. The diagnosis was plugged up EGR pipe. They thought that it could be cleaned out and that would solve the problem. Cost would be $155.00. My car is running so well that I really hate to start messing with it. Are there any dire consequences of just letting the EGR stay plugged? Thanks, BillyC 91LS400 216,000 miles

When your check engine light comes on, do you feel that it is urgent to get your car to the dealer for repair? The check engine light on my 91 LS400 has been on and off for 6 months and recently began to stay on full time. Since there has been no change in performance, I am inclined to just let it stay on rather than take it to the dealer for the minimum $300 charge for changing out a sensor. What do you do when your car's check engine light comes on? BillyC 91LS400 216,000 miles

I'm down to just 2 problems on my 91 LS400, and would appreciate your opinions. 1. The check engine light comes on, stays on for awhile, and then goes off again. There is no difference in the engine performance with the light on or off. In fact, on a recent trip I got my best mileage ever, 26-27 miles per gallon with the check engine light on most of the time. Any idea what is going on? 2. Sometimes the air conditioner cools, sometimes it doesn't. I had the system evacuated and refilled to the proper amount with R-12 refrigerant. No change. When it is cooling properly, the air is really cold, but most of the time the air is just cooled a little. What is there in the system that could cause this kind of intermittent operation? Thanks, BillyC 91LS400 216,000 miles

Looks good. Thanks for the help. Am I in danger of frying something if I don't do this right? BillyC 91 LS400

I had the air bag disconnected on my 91 LS400 and have now reconnected it. Of course the air bag warning light is still on. Anyone know how to reset this light without going to a dealer? Thanks, BillyC 91 LS400 216,000 miles

OK, the concensus seems to be that my starter staying engaged too long on my 91 LS 400 is caused by a sticking solenoid (plunger). Consequently, I have a few questions: 1. Is a replacement solenoid available, or must the whole starter assembly be replaced? 2. How is the starter accessed? 3. Is this a job that a "do it yourselfer" can handle? Thanks, BillyC 91LS400

The starter on my 91 LS 400 is staying engaged for longer and longer periods of time when I first start it in the mornings. Any idea what the cause is and what failure I am headed for? Thanks, BillyC 91LS400 208K miles.

Thanks for the info. I think I will just put it on my watch list for now. Regards, BillyC 91LS400

With the ignition ON and the shifter in PARK, when I depress the brake pedal I get a rather loud click (almost a thump) in the shift console like a relay operating. With the help of this forum, I recently repaired the dreaded hinge/broken black and white wire problem and I thought that this noise was a part of that problem since I did not remember having it before. Apparently not though, since all the other symptoms went away, but this click remained. Any ideas would be appreciated. Thanks, BillyC 91LS400

Good info guys. I repaired the black and white wire this morning and all the symptoms are gone except one. With the shift selector in Park and the ignition switch on, when I push the brake pedal I get a click like a relay operating in the shift console. I don't recall having this sound before the black and white wire broke, so I assumed that it was part of the same problem, but apparently not. Any ideas? Thanks again, BillyC

I haven't had time to trouble shoot this yet, but here is what happened tonight. When I started up I noticed that the "tail light out" symbol on the dash display was on. Then I noticed that each time I put on the brakes, the reverse gear position light on the dash display came on. Later while driving, I determined that each time I apply the brakes, the transmission shifts out of overdrive! Has anyone had this problem before? Any idea what is going on? Thanks, BillyC 91LS400

The check engine light on my 91 LS400 came on last night on the way home from work. It stayed on for about 10 minutes and then went off. There was no change in the way the engine was running. It did not come on any today. I thought that once the Check Engine light came on it stayed on until reset by the dealer. Anyone have any idea about what might be going on? Thanks, BillyC