SCENT

Guys i nee your advise i am new person here. My 2003 Rx300 cant go beyond 1900 RPM During hard acceleration. Even at hill climbing. Kindly suggest or advise me what could be the problem

TrueGS300

There are sure to be codes. Scan for them and tell us what's there

SCENT

Thanks for your reply, there is actually no code at the moment. What happens is whenever my fuel level drops to minimal level a code p0136 will pop up and clears whenever i fill and drive for some time.
But the issue issue of rpm not going above 1900 during hard acceleration persists

TrueGS300

Even if the engine light is not on, there will be codes. That P0136 code will still be stored even when it turns itself off. Was just wondering if any others are there. It would give a big clue. Usually a limited rpm is throttle oriented. But in your case it could be a weak fuel pump.

salimshah

Just a wild guess..
Have some one look at throttle position sensor. This indicates the drivers desire to shift to a lower gear [overriding what the computer would like to do at that rpm] and once the transmission kicks down, the engine sucks more air due to increased rpm and then the cpu allows more fuel into the engine producing more energy.

Salim

simplecar

I say adjust your throttle cable. It may be loose.

maxSteel

I don't understand the description "My 2003 Rx300 cant go beyond 1900 RPM During hard acceleration".
Can you be clarify this a bit:

Can you high-rev it in park?
Does it accelerate and upshift normally, which I think usually is around 2700-3100 rpm?
As you accelerate normally, does the car upshift as it should?
What is the RPM at normal highway speed?

SCENT

Tnks for your concern, i have scan the car again but no code. However, i observe some abnormal condition on the fuel trims. I was just wandering if that could be the problem. At idle, the LTFT bank 1 is always at -15 percent and bank 2 at 3 percent. When the car is raised to up to 2000rpm , this values drops to -4 and --7 respectively. Could this be an issue???

SCENT

I will like to add that the fuel pump was changed recently

SCENT

Tnks Maxsteel, what i meant was the car revs normally to any rpm at stationary, and when i drive the gear shifts normally. However, when i drive, the rpm does not exceed 2000. Its a concern for me because even when i try to overtake i found this difficult as the car will appear not to be accelerating well

maxSteel

It's still confusing.

Are you saying that when you drive and accelerate normally the car is upshifting all the way to overdrive at highway speed without ever exceeding 2000 rpm?
For comparison, here are some other drivers experiences: https://www.clublexus.com/forums/rx-...hat-speed.html

See what happens with overdrive off or with the shift lever in 2 instead of D. It's just not possible to be below 2000 RPM while in a low gear at high speed.
Look at the threads on taking the slack out of the throttle cable, see if that helps.