amicore

Thanks. My idle is ok First about 1000 rpm and after warm up 650 +-50rpm. So can't be fuel pump. I need check all my vaccums line for leaks .Unfortunately no “check engine’ light on toto troubleshoot the problem. I'll check the IAC. Thanks After driving around for a few miles I got engine code "71" (EGR system malfunction). Before all this happend I did changed PCV valve and clean small round filter in EGR modulator. I did other work like changed driver site engine mount (this was a joooob), flush transm ( only Toyota ATF Type IV): replaced leaking air valve in the bottom of power stearing pump(white/bluish smoke for 10 seconds at start-up) flush power stearing system; change differential gear oil; replaced sluggish(not moving well inside jacket) transm. kick down cable(This probably fixed my car jerking at shifting from P to R or D) So did some work but this loosing rpm at parking and at driving too, feels like car is shifting down but is not is slowing down when rpm goes down and back up to same speed back and fourth.Maybe I disturbed something? Loos like some thing is telling computer or what?

Thanks. My idle is ok First about 1000 rpm and after warm up 650 +-50rpm. So can't be fuel pump. I need check all my vaccums line for leaks .Unfortunately no “check engine’ light on toto troubleshoot the problem. I'll check the IAC. Thanks

When in parking and accelerate 1800 rpm car rpm goes down to 1500 rpm and goes up 1800 back and fourth with my foot still holding same pressure on the pedal. Happens over 2000 rpm also. Can't hold still the same rpm and after leting go on gas car shotdown, engine stops. And when driving at the same rpm feels like car go down and back up to speed. THANKS FOR ANY ADVISE.

Thanks for Welcome. I did try Shift lock OD button on end off. Brake stop switch looks like no problem there, checked play on the pedal , light goes on and off fine.

Amicore has mentioned his prob ocurrs whether the car is cold or warm and no mention of a high idle. Thanks, car lately has high idle when cold about 1100-1200 rpm, when worm ( takes some times 15 minutes driving) around 700 rpm and does the same thing cold or worm or maybe a little less jerking at worm I don’t remember before so high idle. After mechanic changed my drive belt I notice higher rpm. I think I should turn down a throttle position sensor like other cars. I don’t now if Lexus has any TPS? I tested GHA--.. advice to when Parking; shift first to N, applying park brake and shift to P. Does the same.

I have 91 LS400 with 160000. So far never shifting problem. Lately during shifting from Park to Drive or Reverse hole car “shakes”, “jerks”, “jumps” a quite bit. Soon in gear no problem to drive. When driving auto shifting up and down normally. Does not matter if cold or worm, same think. Thank you for any advice.