Loosing power when doing full turn or on Idle (1 Viewer)

[Sugar100LC]

Hello Mudders, I have 1999 LC (205K) miles that I recently bought last year and made several upgrades. Recently I loose engine power when I was on idle during traffic, did this twice and I also notice that every time I do a full turn of the steering wheel it will loose power as well. The power goes back when I turn the ignition back on. The battery is on when it does this, as I recently replaced the battery. Any suggestion or idea what's causing it?

Thank you

 

[Dwight S]

Possibly the APPS - (Accelerator throttle lever assembly.) Toyota part # 2206050011.

An illustrated guide to replacing your APPS - Part 1

An illustrated guide to replacing your APPS I've been following this group for a while and it's helped me out so figured I'd give back. I've attached pics from my recent successful change of the APPS sensor on my 2000 LC. This is an easy job (only slightly more complicated than installing a new...

forum.ih8mud.com

I had a sudden loss of throttle when my truck was cold, like my foot slipped off the pedal. Floor it and it would accelerate normal. This happened for a few weeks. Finally, I cranked it up one morning and it immediately went into limp mode and check engine light. P1120 code. Replaced the part and it runs great.

I wouldn’t just go throw parts at it, as the part is pricey. Easy fix as long as long as you can get the three screws holding it on to break loose.

Also, check the online Toyota parts stores. I found the Toyota online price $200 CHEAPER than the NAPA 3rd party part.

1998 Toyota Land Cruiser 4.7L A/T Lever assembly, throttle with sensor. System - 2206050011 | Fred Anderson Toyota, Raleigh NC

Lever assembly, throttle with sensor. System, fuel, injection. 1998 Toyota Land Cruiser 4.7L A/T. Genuine Toyota Part - 2206050011 (22060-50011, 2206050010). Ships from Fred Anderson Toyota, Raleigh NC

parts.fredandersontoyota.com

 

[Sugar100LC]

Thank you @Dwight S this is helpful.

 

[abuck99]

APPS going bad or gone bad likely throw a CEL or at least store some codes that you could pull via Techstream.

First - Id check the idle speed control valve that is mounted to the power steering pump. If this becomes plugged or fails it will cause the engine idle to drop or die while turning.

 

[saucebox]

APPS going bad or gone bad likely throw a CEL or at least store some codes that you could pull via Techstream.

First - Id check the idle speed control valve that is mounted to the power steering pump. If this becomes plugged or fails it will cause the engine idle to drop or die while turning.

I'd check that first also. Side benefit of being a much cheaper part if it is what failed you

 

[Sugar100LC]

Thank you @saucebox and @abuck99

 

[Dwight S]

APPS going bad or gone bad likely throw a CEL or at least store some codes that you could pull via Techstream.

First - Id check the idle speed control valve that is mounted to the power steering pump. If this becomes plugged or fails it will cause the engine idle to drop or die while turning.

No codes on mine until it failed completely. I had a few weeks of cold start, power loss and recover by flooding it. Some days, no power loss at all. Ran fine, otherwise. No CEL, no stored codes on the Scangauge 2. When it failed, it was when I cranked up for work. Went into limp home immediately. No coming back up. It was done.

 

[abuck99]

No codes on mine until it failed completely. I had a few weeks of cold start, power loss and recover by flooding it. Some days, no power loss at all. Ran fine, otherwise. No CEL, no stored codes on the Scangauge 2. When it failed, it was when I cranked up for work. Went into limp home immediately. No coming back up. It was done.

Not debating your outcome. OP’s symptoms point towards IAC. Guess we’ll find out soon enough.

Btw Scanguage II will not show stored system fault codes- only the “P-“ codes when CEL is triggered. The stored system fault codes require plugging in with Tech-stream in order to see them. These are fault codes that don’t throw a CEL but give a history of pending issues.

 

[2001LC]

"The battery is on when it does this" If your referring to battery "light" on dash. This may be due to engine idle (RPM) dropping so low, alternator spinning to slow for adquite charge.

Inspect all vacuum lines.
Inspect for throttle body & intake manifold gaskets for leaks.
Check that air filter box/air tube and all it's fittings & tubes intact are properly fitted and snug.
Check air filter and it's box for obstruction.

Than I'd reinspect idle-up.
1) Inspect the double vacuum line, making sure good snug fit at all 4 ends and no breaks or holes in either line.
2) Check inside vacuum lines for any signs of fluid.
3) Make sure no obstruction in either vacuum line.
4):
AIR CONTROL VALVE
INSPECTION
1. TURN AIR CONDITIONING SWITCH OFF
2. CHECK IDLE−UP
(a) Start the engine and run it at idle.
(b) Fully turn the steering wheel.
(c) Check that the engine rpm decreases when the vacuum
hose of the air control valve is pinched.
(d) Check that the engine rpm increases when the hose is released.

 

[Sugar100LC]

Thank you @2001LC, very informative.