93ls400walt

Maybe the erg code was never cleared. Clear it by removing the neg battery terminal clamp for a couple of minutes. There is a fuse you can remove so you don't have to reset everything. But I am not sure which one it is. Be sure to disable or know the activation code for you stereo before disconneting the battery. Code 41 is for the tps itself or the wireing harness, But as most codes go, the final prob. may be the ECM. Look at www.lexls.com for advice on adjusting the tps. You can buy a new tps from park place lexus in plano, texas for $75.00. www.newlexusparts.com The codes narrow you to the system failure. The a service manual will lead you through the sequence of testing, Mainly ohm and voltage testing of each sensor or part. Look at www.bgprod.com for info on having your erg system cleaned.

Welcome! If this is happinging on " damp " days. I would look for a shorting out wire. In the dark you may be able to see arching. Or at least hear it. When the car is acting up. Lexus and other places sell BG44K. A fuel and intake cleaner. Look for part # 208 for the in tank cleaner. Around twenty dollars. Also BG has a spray throttle body/plate and Idle air control valve cleaner. The kit from Lexus today was $40.00 for both. These may help with your overall preformance amd idle. Look at Bg's web site www.bgprod.com for more info. Idle probs seam to be a common prob. Please let us know your results Walt

Congratulations Blake, I have always appreceated your knowledge and comments on these threads. Walt

I found on th UK LOC site a notice of the mag., CAR MECHANICS, that the August issue will feature an article on the Ls 400. The web site came up: www.carmechanicsmag.co/uk/. After a goggle search for car mechanics magazine. You will be able to order it on line Jule 21st.

Another area to look at could be the water valve. Located on the fire wall behind the throttle cable cover. Make sure that the lever moves when changing from MAX hot to MAX cold. And that you feel the air temp from the vents to corrospond. The part will have heater hoses going in and out. With a cable attached to the side and connecting to the lever arm. You can unsnap the cable and move the are by hand. And check the vent air temp also. The manual states to Adj. 1. Remove control cable. Disconnect the clip and cable from the water valve 2. SET AIR TEMP TO MAX COOL a. turn ignition switch On. b. set the blower switch On. c. set the Temp. switch to MAX COOL 3. set the water valve lever to the max cool position. eg. feel the vent air temp. Then reinstall the cable and lock the clamp

The factory manual states for on the car checking of the IAC. Listen for a clicking sound from the IAC when the engine is shut off. If no clicking, the unit needs to be removed and checked for mechinical function and electrical specs. Also, I did not read about anyone looking at the DP ( dash pot ) function. in regards to stalling. I beleive this unit buffers the deceleration of the rpm. For a more gradual return to normal idle speed.

Well it's done. Thank you all for your advice. I truly could have not done this without it. I still have my acceleration problem. It is somewhat better though. I did find that I could set the adjustment with the .40 blade. But would not achieve the second reading after changing to the thicker blade. The reading did not change. So I saw the there was free play on the throttle plate from the set screw stop before the throttle plate would start to open. so I held the stop arm to the position to where the plate was just starting to open and adjusted the stop screw down to it. It was at least 4-5 mm off. So now the throttle response is GREATLY improved. And my orgional prob. is some better. I still have it. I guess I'll look at fuel pressure next. I have not cleaned the MAF. I have a spray can of electrical contact cleaner for cars. Does any one know if this is safe to use on the MAF wires/transisters ? My O2 sensors don't throw a code. But what kind of acceleration probs. can these cause ? Thanks, Walt

Any one have any malfunctions of their IAC or DP? If so what problems did they cause in your cars preformance? Also where and how do you adjust the idle speed? And where does your car idle at? The manual says 650 +/- 50. My warm idle in park is just short of 600. And in drive it's right at 450. Both without the a/c on. ( IAC= idle air controll valve ) ( DP= dash pot ) Thanks, Walt

Good deal! I have a 93ls also. It is a great car. I do have some minor so far annoying probs. now and then. But so far they have been cheap and easy to fix. Good luck.

Park place in Lexus in Plano, Texas. www.newcarparts.com. You can scan their list of parts and prices. The Lexus dealer in Lexington, Ky wanted $150.00 for a TPS. PPL sold it to me for $75.00. No tax or shipping charge. I call that a great price. CORRECTION; The web site no longer comes up under the above newcarparts.com. It now comes up under www.newlexusparts.com It should bring up Park Place Lexus. In Plano, Texas

I'm having a simular prob. But it is at any rpm, If i accelerate to fast. Engine runs fine otherwise. If I press the gas faster than a smooth/steady push the rpm drops. And the feel of the car is like you are putting on the brake lightly. I get a " puff " like noise from under the hood. I also replaced my undercarriage gas filter. And by chance when I ordered it from the dealer. They sent the in tank filter instead. So I paid and kept it and ordered the right filter. No change in the car after changing the undercarriage filter. I to plan to change the in tank filter. My car throws a Code 41. Which is a error for the throttle speed sensor. I ordered the sensor ( 74.00 ) from Park Place Lexus-Plano, Tx. www.newcarparts.com. It's supposed to be here 7/3. I hope this solves the issue. Be sure to order a new fuel pump gasket before you take everything apart. I'll post results from the TPS change.

Josh! I stand behind you and your duties. Be proud of who you are. And what you will be doing. And always remember to never take your safety for granted. Always on guard. My Son will be there shortly after you. Sometime in Oct. Exact spot yet to be announced. He is a Blackhawk power train mechanic. Peace and safety be with you. And a safe trip home. Walt

Thank you both for your info. It is very helpfull. I will order a tps asap. And report my results. I am wondering what, If any, problems your cars were having? My check engine light never came on. I checked for codes because of the acceleration problem. Walt

MY 93 Ls with 101,000 miles started to lose power on acceleration under a load. Such as A/C on or going up even a small incline. Or would drop the RPM if I tried to accelerate to fast. The engine dosen't miss fire or make any noise except a puffing sound when this happens. Sort of like a sneeze. If I am under 2000rpm, the engine will drop and increase the rpm repeatedly untill I let off the gas pedel. If I am over 2200rpm the engine rpm will drop to around 1200-1500rpm and stay there untill I let off the gas pedal. In park or neutral, the engine rpm will go up to 6k plus. Smooth and easy. Also while driving the engine does fine if I only accelerate slowly. If I push the gas down as if to pass someone. The rpm drops far enough as to slow the car as if I'm braking. The problem slightly improved with two new coils. And denso Ird. plugs. I also replaced the under car fuel filter. I had replaced the wires, caps, rotors and plugs 8000 miles ago. I changed the plugs again because I used Bosch Platinum then. And have read about fouling prob's with them after 6K. The electrodes looked ok, but there was browinsh staining around the outside area above the tighting ring. Looked as if there was a leak of combustion gas. The engine is much more responsive and smooth. The problem is much less. But still there. After that long story. The code readout is code 41. The TPS and or ECM fault code, and or the tps wire harness. Before the Dealer call, I will replace the Tsp sensor. Anyone ever do this without removing the throttle body. If so, How did you connect your Ohm meter? Also, any info on checking or replacing the wire Harness? The protective cover on mine looks as to have been melted to expose the wires. And the coverings on two of the 4 wires look mangled and are stiff to the touch. I looked at lexls for the tps adj. by hand, with trial and error. But it dosen't make sense to me. The tps adj. seems to be for an opened/closed setting using an ohm meter. Regardless as to what the idle speed is. Lastly, Any thoughts on this problem other than the tps?

There are many post on this issue. You will find all you care to know by doing a forum search with keywords.

Threadcutter! It's a good thing that " I'm in a period of transition "

I cycled through all of the vent buttons. And have not heard the noises since. May have been a stuck flap. Thanks

An EPIC saga, with a great ending. Thank you also for all of the info on what did and did not work. Prior to your last post. I wanted to clean and fill my 93ls, but was a bit scared to poss. get into the problems that you had. Now I am looking forward to getting the reward that you have obtained. Thank you!

Yes, my 93ls lighting was perfect. But my tach seldom worked. Sometimes with a fast acceleration from a stand still my tach would rise, but never above around 2200rpm, a false low. The tach was however more responsive while using the ECT. But still low. As far as hitting the dash above the gages, all that did for me was give a dash squeak. Which did improve after removing and re-installing the IC. My spedo. worked 99% of the time. But did stick sometimes. Of some intrest to me is the fact that after replacing my IC with a used, but working tach/speedo units, The needles on both stuck three times the first week. Popping up after reaching around 1500rpm. But have been without problems since. Combine this with the hitting the dash solution. Makes me think a connecter contact issue on the back of the IC should be looked at. Maybe a cleaning with electrical contact solution would help. A simple thought, but no real cost involved.

My 93Ls has 95K on it. Bought it 11/05. About one month ago started hearing a strange sound like from behind the glove box. only after stopping at lights, ect. with engine at idle. Sounds kind of like a mechanical gear turning or closing. I thought that it may be an ECU resetting. Now, today the sound has progressed. It sounds like a gear clicking or slipping. And sounds more like it is behind the center counsel air vents. I can best describe the sound as like a computer hard drive hanging up or sticking with a sliding/clicking sound. I have not noticed any adverse problems with the car running or driving. Any thoughts?

Thanks for your replies. My Ls is a 93 with 95,000k on it. The rubber hangers are connected. The mufflers seam to be up and at a good height. But I think I will replace them anyway. Don't want to keep damanging my muffs.

Any suggestions on ride height? I live up a steep driveway. When I first bought the car 6 months ago. I could go up the drive with 1 or 2 passengers and a full tank of gas and not drag the mufflers. Now with just myself and a full tank, the mufflers drag.( No I did not gain weight ). Any rear suspension parts to inspect? or replace?. The car seem to sit at a proper height with no load. But the rear lowers quite a bit with any added weight in the rear.

Sweet! here's my white one.

Welcome, and sorry. This is an issue, I think mainly on the 93-94 year LS 400, with the tach and spedo. I hear that is is an expensive dealer fix. There is question as to wheather the malfunctioning gauge/s can be fixed. My friend bought a used IC ( cluster assembly ) that the tach worked on and switched it out with his. Then you have to deal with the odometer reading setting. Used IC's go for around $300.00 and up. And there is no guarantee how long they may work. There is a lot of discussion on the threads here on LOC. Do a search for tach or instrument cluster. To find repair offers and more info.

Cleans up nice! And a great choice of rims.