I have an 07 RX 350 and I notice when I start the vehicle up and let it idle for a bit and every time I just turn the steering wheel slightly the RPM go up. I'm not sure if this is normal with RX's, I don't notice it with my other vehicles. The RX runs fine, no problems, I just found it strange. If anyone has any insight on this please let me know.

Thanks

 

normal and I see it on 99% of cars...

 

Sorry for being naive about this, but do you know the reason why the RPM's go up when you turn the steering wheel?

Thanks

 

I believe because it senses a drag on the motor pulling the RPM's down under its preset limit when you turn the wheel (cause it takes power)---thus raising the idle up to compensate for it? my best guess.

 

powersteering. don't worry about it

 

Another question comes to mind that how come (most) other vehicles don't do this ??

The answer lies in ULEV ... ultra low emission ... every drop of fuel is held back unless it is needed. RX.

Salim

 

Every car that I've ever had with power steering, the idle does go up slightly upon turning the wheel. It's more noticeable when the A/C is on. As someone said above, an engine idles at a specific RPM point in order to conserve fuel and prevent un-needed stress on the engine and it's systems. Since many vehicle systems, including the power steering pump, are powered by the engine, it has to work a little bit harder when a system is called upon to do something, such as turning the steering wheel or switching the A/C on. Other systems that don't involve the engine or don't require as much engine draw won't cause changes in idle, such as pressing the brake pedal, or using the windshield wipers.

 

If your vehicle is idling, there is more of a load to move the steering wheel. Toyota's new electric power steering unit dont have this problem.

 

Thank you guys for enlightening me on this.