LB Lex

My car is mostly normal (93 GS300), but the idle is a slightly choppy. I cleaned the TPS (throttle position sensor) and placed it back onto the throttle. I used an ohm meter to set it according to posts I've searched on CL, and the sensor does not seem to be working right. Example: No matter how far I rotated the sensor clockwise or counter-clockwise, the ohm reading never displayed a zero. The maximum reading I obtained through various settings was 7.5. The lowest reading was 4. With these numbers, it seems that the sensor tells the computer that the throttle is always partially open (because the reading for closed throttle should be below 2.3k ohms) and that full throttle opening neve occurs (because the maximum reading should be 10k ohms). Here is the link to the information I obtained: https://www.clublexus.com/forums/att...&postid=423703

Is this the wrong information? Is my TPS okay? How can I test it with a ohm and voltmeter?

Any help/suggestions are greatly appreciated.

DevilDog

Are you sure your checking the correct pins? Also, If memory serves me right, your suppossed to use a vacuum pump to pull the vacuum dashpot closed before checking any adjustments. The dashpot is the one mounted to the t-body with a hose going to the t-body as well.

PM me your e-mail and fax number. I'll see what I can send you to properly check and adjust the TPS. Probably won't happen until monday though.

DD

LB Lex

DevilDog, thanks for your help. Here is my email address: xxxxx I didn't know anything about the dashpot, maybe that is the problem, but the throttle was resting against the stop.

Lvangundy

Fo anyone who doesn't know here is some info on a vacuum dashpot.

http://www.jaimekop.com/CarbManual/Page26-27/

I think I know what it is, because I've removed it in an unsuccessful attempt to take off the throttle body. It looks like a miniature motor mount? Hasa rubber boot and the pin can be slightly pushed in right?

How often should these be replaced?

DevilDog

93LexoGS300,
Check your e-mail. I just sent you a 12 page detailed description of your t-body assembly and how to check it. Let me know how it goes! If anyone else with the same car wants a copy, pm me your e-mail.

DD

DevilDog

Gundy,
Your t-body set up is entirely different. Don't worry about your dash pot. I've never seen one go bad.

DD

LB Lex

DevilDog, thanks a lot for the instructions! They are very helpful.