Lexus Gs400 Transmission Problem?

[preetpay]

Hi, I have a 2000 GS400 Platinum Series with 34k miles on it. I am having problems taking the shifter out of park. The shift knob is extremely hard to move. Finally when I do get it into drive, I press the gas and nothing happens, I can push the accelerator to the floor with EASE and it won't even rev. Sometimes, it runs fine though, but the shifter is always hard to get into drive. Could this be a cable problem or a transmission problem? Thanks

[GuyTelefunken]

When you press the brake (in park) a small click should be felt in the shifter area. This is the electromagnetic solenoid retracting that releases the shifter handle, allowing you to change gears. Assuming this is working, if the shifter is hard to move from gear to gear, you most likely have something seized (rusted) or jammed in the linkage or in the transmission.

If the car doesn't move in Drive, is the gear position indicator on the dash showing "D"? Either way, you have a 4-year 50,000 mile bumper to bumper warranty, as well as a 6-year, 70,000 mile warranty on the powertrain, including the transmission. Go get some free service!

[preetpay]

Thanks for your reply. I am not eligible for a warranty because my car has a salvage title. Does anyone think this could be an electronic problem? I can slam on the gas and it feels like the pedal isnt even attached to anything. The engine won't even revv. Thanks

[SKperformance]

You obviously have an elctrial problem from the pedals to the computer.

Do the taillights come on when you press the brakes when you are having a problem?

[preetpay]

Yes the brake lights work.

[GuyTelefunken]

Salvage title, ouch. I have to ponder what the nature of the damage was to get you the "Salvage Award"?

Ok, here's the scoop. You're going to do this from your own pocket.

Engine Revving: You press the gas, the pedal drags the throttle cable, it moves the throttle pedal position sensor on the throttle body. Signal goes to ECM, signal goes back to throttle motor, throttle motor moves as instructed by the pedal, throttle position sensor reports back to ECM the position of the throttle plate.

If there is a problem with the throttle position sensor (TPS) or the throttle pedal position sensor, the entire throttle body may need to be replaced. The TPS on a 400 or 430 is not a servicable part, but the pedal position sensor may be. Either way, it is "Lexus only" when it comes to testing and replacing (the need to calibrate the computer to the new sensor). Though you could just change out the entire throttle body with a used one and probably need no major adjustment, besides removing the battery cable for 5 minutes to clear the adaptive throttle maps. After you have had a proper diagnosis, if throttle body replacement is necessary, be prepared. New cost is in the vacinity of $1200! :cries:

As for the transmission, get that baby up on a rack and start looking. If you disconnect the shift rod between the floor shifter and the transmission, you should be able to determine if the binding is in the trans. or the shifter assembly. If it's in the trans., proceede to your nearest transmission repair shop.

It does sound like you have 2 seperate problems; one with the trans. and one with the throttle.

See the attached pic for disconnection of the shift rod.

[preetpay]

Thanks a lot for your reply. It really helped me put two and two together. I forgot to mention that sometimes the car will revv fine and the accelerator will go down. If it doesn't push down, I turn the car off and restart it and it works fine. Maybe you can make something of that. Thanks

[GuyTelefunken]

Are you saying that the pedal sometimes does not go down? If that is the case, take a look and find out what the heck is jammed. I'm not sure if I understood what you wrote in your last message.

P.S. Hope you got this car cheap!

[preetpay]

Sometimes, I push the gas pedal and it works. Other times, i'll press the gas pedal and it'll go straight to the floor with no effort. It is as if it's not connected to anything. But, if i start the car again, it'll be fine.