ericjcline

hio-

yes, i searched. and searched. and then a couple times more. issue is on a GS300, 1999, with ~178K miles. had the car about a year.


when i hit the pedal, i get a lag and then gas. it manifests as a lurch that is not at all acceptable in a luxury car. i tightened the cable to the point that the car had trouble shifting down when coming to a stop and then loosened the nut until it would shift down normally. there remains a touch of slack, which i would expect should be there.

so, i am starting to look for other ways to tighten things up. would a new TPS help? i am wondering if a tighter return spring might help the issue, but i'd rather find something i can try with a wrench before i try with a credit card. any suggestions are greatly appreciated.

TIA-

-e

Sphan519

Try changing the motor mounts and transmission mount, I just switched mine, my car has 190k miles and it feels like a brand new car now. My car before had a slight hesitation, now it's a smooth immediate throttle response.

ericjcline

thanks sphan, i will put it on the list.

did you notice any tears in your mounts after removal? i am wondering how much slop you noticed. my old land cruiser didn't seem to care if the motor mounts were torn or not, it just kept sloggin away. i'd expect more sensitivity to any slop in the lexus.

Sphan519

Both my motor mounts and transmission mounts were broken once they were pulled out. Since my car is a V8, it was still smooth, if you didn't know any better you would think there was nothing wrong with the car. Night and Day difference once i changed it.

ericjcline

interesting. i will definitely look into it.

in my thinking about this, does it make sense that i would only see the accel slack from a stand still, but not when i put my foot into it when already moving? i'd think i'd notice some slop with any significant acceleration, but i don't. thoughts?

TableSyrup

Also check with the car in park, push it forward and back, see if it moves substantially back and forth before catching.. which would indicate play in the transmission or diff....

I'm replacing my diff tomorrow... has a ton of play in it.... also causes a perceived lag type situation.

ericjcline

not motor or trans mounts. all are good and look relatively recent.

not transmission. in park, it doesn't move at all.

so, i grabbed an OBD reader for grins and tapped the gas to watch the TPS and AFM. turns out, i didn't get a consistent TPS response with every tap, and the AFM didn't respond a couple of times too. so, i am thinking i need to chase down electrical gremlins. i also notice the hesitation is much less common and i couldn't repeat it consistently today after all our rain blew out over the last day or so. i am wondering if maybe there is an electrical short somewhere.

anybody have a good source on a used TPS or AFM? it'd be good to try out a different set to see if that makes a difference before i drop the coin at the dealer.

thanks!

Category5

motor and trans mounts for hesitation.... interesting, is that because the slack that the torque of the motor and trans travel which we would feel as hesitation? trip if so because I know mine are both TOAST

sivikvtec

You might try contacting the dealer to see if the TPS is considered part of the throttle body assembly. It would be fixed for free because of this:

www.toyotaelsettlement.com/Home/FAQ

Category5

it is indeed a part of the throttle body, you can replace it as well

Category5

and by all means it is not fixed foe free for any reason at all lol..... I wish! unless of course you have some killer warranty lol... btw OP have you tried taking your OCV valve out and cleaning it as well as its screen? a def. culprit to our hesitation problems... as well as taking your throttle body off and cleaning the heck out of it and your mass air fs

sivikvtec

Depends...Read the link and search in the performance subforum. People are getting throttle body assemblies replaced for free at the dealer regardless of age/mileage. Details are in the FAQ link I provided.

Obviously, this is only worth pursuing if OP is sure the TPS is bad.

Category5

im sure it is its a very very common issue, can diagnose it with a simple voltmeter... I went changing one thing after another to get that dam code to clear and outta limp mode. sure wish i knew then if its indeed a free fix, what 70% of club lexus ends up battling lol

ericjcline

its funny, it doesn't show a CEL, so i am a little surprised the TPS is acting up.

i will check into the suit. it might be worth it to have lexus diagnose the issue so i don't go chasing expensive sensors all around.

i had the throttle body cleaned out when i had the igniters done about a year ago. it was squeaky clean in there, so hopefully that isn't an issue at this point. we shall see...

ericjcline

its funny, it doesn't show a CEL, so i am a little surprised the TPS is acting up.

i will check into the suit. it might be worth it to have lexus diagnose the issue so i don't go chasing expensive sensors all around.

i had the throttle body cleaned out when i had the igniters done about a year ago. it was squeaky clean in there, so hopefully that isn't an issue at this point. we shall see...