AlexusAnja

If fuel pressure issue, then would it not happen when I put into neutral and rev just the same? I've tried putting into neutral and it goes to redline without hesitation.

I'm just at point where I'll just say "hey, drive like a normal person..." and not worry too much about having to gun it. Just bothers me in back of my mind to know that if I ever did have to "gun it" that I won't be going anywhere until I ease off a little...

Nad1370

I guess you need more knowledge in fuel delivery.

I'll go short version here:
Ecu controls fuel delivery. It needs to see load, throttle pos., air intake MAF. ect...
Reving the engine in neutral has no load in it. Like spinning a bike w/ wheels of the ground.
Now attach a 4000lb mass onto it and see if the revs go as fast.
Not so fast huh?

When the vehicle is put into a lot of load. The duration of the injectors stay open longer to deliver proper amount of fuel. If you don't have enough pressure. The engine will hessitate and jerk as your experiencing coming of a stop under high load demands.

Hope this enlightens you and see how fuel pressure can affect drivability.

AlexusAnja

Wow... good to know.

Looks to be a dealer check for me then... thanks all.

jbl-1985

Had the same problem with my 300. Car would run like crap - revving everywhich way. Throttle not responsive sometimes. Threw a code for the Throttle Positioning Sensor (forget the actual code #) - replaced it and all was perfect again.

L3XOTIC

02 Sensor
Knock Sensor
Plugs

Some of the possibilities. Really tough to tell. Just because it throws a code also doesnt necceseraily mean itll be a easy fix. I just put almost $800 toward my RX cause one code would go away and a new one would come on. I had the SAME EXACT issue as yourself.

It ended up being BOTH knock sensors, oxygon sensor and a transmission part that was about $150 that helps it to shift on time. Hope this helps, a bit?

Francis

Sound likes mine before. I DIY/replaced the tranny fluid with the factory fluid last year. Then I realized the respond was very slow. No code found and I thought the fluid level was fine. At the end, I brought it to the dealer to see what was wrong.
At first, they said the fluid was way overflow and they had to replace the fluid before they started diagnosis the car . After they replaced the fluid with the right level, the car ran fine. GL

PJ82ND

Fuel psi regulator or a fuel pump or bad ground on fuel pump if ur around nnj hit me up i got a techstream lexus oem perks of the job :-)