mcantlin

Car model ls400, year 1994, 84000 miles

Car went in for repair of EGR tube which required transmission to be dropped. Tune-up and steering pump replacement also done.

Car now jerks when shifted from park into drive. Also may be more jerking (hard shift) when it goes into other gears but is not as noticable. Idle seems fine. Acceleration seems ok but I can't seem to get it to jump into high rpms by fast full throttle from stop. Car does accelerate but does so in higher gears.

I suspect sensors.

Right? Wrong? Leads? Anything?

Thanks

mlevk

mcantlin

I have a 91 and 3 weeks after I bought it , I had a rear main seal leak. Well you know that the tranny has to come off .

It was replaced under a warranty from the used car dealer, not LEXUS, and they used their "mechainc" shop to do the work.
Same problem you have. he tried to correct for 2 weeks ,
but to no avail. He checked every sensor, mounts, etc. The tranny shifts hard into D from PARK.

The shift from 1st to 2nd is HARD under LIGHT acceleration and NORMAL under HARD ACCELERATION. If I STOP at "R" momentarialy and then in to "D" then the engagement is soft.

It's been 2 years and 38K , so I used to it , but its still there.
The LEXUS dealer says he has to take it out again , but can't
say what is causing it.

So if anyone knows ?

Ca12los69

Try checking the Throttle cable that goes from the Throttle Body to the transmission. It may have been broken at the point where it connects into the tranny. You have to drop the oil pan. Remove the solenoids and other vavle body covers in tranny. you should be able to see where the cable hooks on to the throttle valve. Maybe it's loose or broken. If this is the case then the Tranny is sensing that the throttle is open completly, thus harsh engagement at low speed or idle. But once you floor it the engagement is smooth due to fact that the throttle really is fully open. LET ME KNOW

dahan

it happen to me in my 1995 ls400,the problem gone after adjusting TRC snsor >>>>>>>good luck

mlevk

Wow , a 2 year old thread and I still get a reply ! That's great.
Now I need to know what a TRC sensor is and how to adjust it.
It's not the THROTTLE POSITION SENSOR is it ?

Ca12los69

I have had the same problem for 3 years now!!! I am getting sick of mechanics telling me I need a new tranny. I also had this problem right after the egr pipe replacement. Did you mean Throttle Position Sensor?

NC211

I have a 95 ls400 w/ 90k miiles, having the exact same issue! 90k service has already been done "fluids FLUSHED" and everything. What is a TRC Sensor? Anyone???

Ca12los69

My harsh engagement has been solved. The problem started when the EGR tube had to be replaced. It turns out our private mechanic did a horrible job. From what the guys at Lexus told me they said the guy removed the tranny without first unhooking the throttle cable at the throttle body. by doing this he damaged the throttle housing inside the transmission, this effected the hydralic pressure causing it to rise because it sensed the engine was under moderate acceleration, thus the tranny speeds up to meet the engine speed. It only cost $100. This is what happened to most of us, this cable just gets tugged on enough to loosen the cable on top left side of the tranny.
good luck

mlevk

Thank you ,

I'll take a look this weekend to see if they did the same thing on mine.

MJHSC400

"My harsh engagement has been solved. The problem started when the EGR tube had to be replaced. It turns out our private..........."

Was it also shifting hard into reverse from park/drive, and from drive to reverse because of the tranny throttle body housing????? I have the same thing going on too--

Thanks

crazimofo

I have this as well..

is it a new THROTTLE CABLE that solves the problem? is that what everyone is saying? part number anyone?

let us know.
thanks

KA8

iTrader: (1)

Sorry to bump an old thread but I have same symptom. Jerking going from P to D but when I stop at R then D engagement is very smooth, just changed to fluid to type-4 tranny fluid. I know my LS had engine rebuilt 3 yrs ago and maybe they messed something up? Thanks in advance.

ssdoeg2

I recently worked on my 1995 ls tranny that would not engage at all and had some of your symptoms. Hope I can explain without getting to confusing or rambling. I flushed the tranny myself and put in type IV fluid and tranny started working somewhat but still slipped so at the least change your filter, do a drain and refill with type IV fluid and see what your symptoms are at that point. If you are still having shift engagement problems it may be a sticking shift solenoid. My LS also had a harsh P-D engagement and when I did the voltage check on my shift solenoids, the #3 solenoid was sticking. I cleaned the solenoid, reinstalled it and it shifted much better. Let me say that when I flushed my tranny it had the wrong fluid and the filter was really filthy so it probably still needs to be cleaned again till the valve body is completely clean of debris. I think that solenoid is sticking again so I need to drop tranny again to clean it but it's being painted right now so that's on hold.
Ohm out all your solenoids first, then do the voltage check if they're all good ohm wise. See where you're at after this.

KA8

iTrader: (1)

^
Thanks for your help. I did some searching and I found throttle cable was installed incorrectly when a mechanic messed with the cables when getting to a leaking coolant hose. Now it shifts like it should.

willhickey

iTrader: (1)

what do you mean incorrectly? my ls and sc o this hahaha and that line has been off both