2006 LX-470 Idle Adjustment (1 Viewer)

[MUDZLLA]

Hey guys/gals/LGBTQers...
Anyone know how to adjust the idle on the 2UZ-FE with VVT? My engine races to around 1800 on start-up and settles down to 1050 when warm? Also seems to jump around a bit. Spec calls for around 700. New to this model so not sure if I need to patch into the computer or there's an adjustment screw somewhere. Any help would be appreciated.

 

[Trunk Monkey]

Try cleaning the throttle body and MAF, disconnect the batt, and let the ECU relearn.

 

[ramangain]

Also double check the idle speed with an appropriate OBD2 sensor and reader. If the tach has EVER been touched, the internal spring can move from its carefully coiled position and read incorrectly. Don't ask how I know this ....

 

[OEMGUY0720]

The 2uzfe unlike other inline4 or v6 toyota engines have an idle-up actuator. The ecu controls the idle on the 2uz based on a few factors like the throttle body, maf, coil and sais (if applicable) electrical signals. Maintain these and you should be able to bring it back to factory 750-800rpm at optimal engine temps with or without aircon turned on.

Ps, add vacuum hoses to things to check all are in good working order.

 

[MUDZLLA]

Try cleaning the throttle body and MAF, disconnect the batt, and let the ECU relearn.

Will do! Thanks.

 

[MUDZLLA]

Also double check the idle speed with an appropriate OBD2 sensor and reader. If the tach has EVER been touched, the internal spring can move from its carefully coiled position and read incorrectly. Don't ask how I know this ....

How do y--- ohh right. Well thx but I can hear it scream at start up so pretty sure it's not a wonky tach, but thx good to know.

 

[MUDZLLA]

The 2uzfe unlike other inline4 or v6 toyota engines have an idle-up actuator. The ecu controls the idle on the 2uz based on a few factors like the throttle body, maf, coil and sais (if applicable) electrical signals. Maintain these and you should be able to bring it back to factory 750-800rpm at optimal engine temps with or without aircon turned on.

Ps, add vacuum hoses to things to check all are in good working order.

Yeah I was checking vac hoses and noticed yellow paint on the idle up vacuum switch. It may have been replaced. I can pull one off my 98 I just installed and see if it helps. It's such a simple switch - high pressure and it opens the vacuum switch. Hard to see how it can get stuck open sitting in PS fluid all day. Usually the little plastic vac tube connections just break off. But definately need to follow all the vac tubes. Any good way of testing for leaks besides lighting a match beside it?

 

[OEMGUY0720]

Yeah I was checking vac hoses and noticed yellow paint on the idle up vacuum switch. It may have been replaced. I can pull one off my 98 I just installed and see if it helps. It's such a simple switch - high pressure and it opens the vacuum switch. Hard to see how it can get stuck open sitting in PS fluid all day. Usually the little plastic vac tube connections just break off. But definately need to follow all the vac tubes. Any good way of testing for leaks besides lighting a match beside it?

I think the best way is to physical inspect it as cracks as small as a hairline can affect it and can barely be noticeable on idle pressure/rpm. One thing I noticed when I overhauled my 2uz intake ports, intake manifold assembly w/ new oe gaskets, throttle body assembly and oe gasket, maf and all vacuum lines was the idle became unbelievably fine smooth as silk. Pictures below of what I cleaned or decarbonized.

 

[MUDZLLA]

Wow nice! How did you decarbonize the intake port?

 

[OEMGUY0720]

Wow nice! How did you decarbonize the intake port?

I just used a carb cleaner. 2 cans of it on the intake manifold assembly and another 2 cans for all 8 intake ports (most of that carbon was fossilized as hard af).