Quanzinjer

Hi all,

first and foremost I am new to clublexus, and am hoping to have followed the proper etiquette for my post, but apologies if not.

My 97 ls400 has been throwing the p0510 closed throttle position switch, with a DTC severity of 2/3. I replaced the TPS sensor, but this code still arises.

I experience issues such as low idle in park (1000rpm or less) and in gear (300-250rpm). Rough shifting between gears and rough downshifting when braking. Turning on AC makes a small difference but doesn’t get the rpm’s to 650 idle.

this is the only code I have and have been attempting to fix the root cause but haven’t had any luck. I do have a mechanic appointment in the near future, but I was curious if any of y’all have experienced this and could give any input.

paulo57509

When you installed the new TPS, did you re-adjust the TPS closed position?

The other symptoms you describe could very well be caused by the TPS out of adjustment.

Quanzinjer

I attempted to adjust/tune my TPS with a multimeter a week ago, but do not have the proper alligator clips to get to the sensors pins. since this is my only mod of transportation, I eyeballed the adjustment near 650 rpm’s and have been driving in that current state.

I have been driving with the eyeballed adjustment for the past week with the rpms staying near 650 rpms and no CEL. Only recently on a drive home did the idle become very low on start and then the CEL came on mid commute.

do you believe this could all be solved with a proper adjustment to oem specs?

Thanks for the help!