Chronicles of a High Idle Post Tune-up

yep, took me a while to find it so I figured I'd share.

got a genuine Toyota tps for $25 shipped lol

it came in a Toyota box so I think its some guy at the dealership stealing and selling parts on ebay but hey its brand new oem so I don't care where it came from as long as its original.

 

Don't ask don't tell

 

Hey OP! Wanted to ask you more details about your hot start issue. Was there any consistency to it - meaning, did it only occur at certain time intervals?

In our case, it's been always at the half hour mark. If truck is full op. temp, then shut off, with hood down, then ~30 min later, it's excessive cranking. But the weird thing is, then once it starts, if you shut it off then try to restart it immediately after that, it starts right up. One of the mechanics that did a good amount of work on it felt that the hot starts were worst at the hour mark, but we always noted the 1/2 hour mark being the problem.

Anyway - just wondered how similar/different our problems were with starting, and also wondered how your situation is coming along. Wishing you the best!

 

No time interval for me. Starting effort used to be directly proportional to engine temp.

 

Ah, I see. So proportional to engine temp - what was it when the starting problem occurred? Was it an elevated ECT or elevated IAT that seemed to coordinate with your issue?

 

As best as I could tell, an elevated ECT. I don't exactly have a scientific basis for this, but I never even considered IAT as a problem. I just looked at the coolant gauge and knew it would be that hard to start.

 

Gotcha. Sounds like overall, its a bit different from our problem, but I'm still hopeful this could be it for us too. Who knows - maybe when they malfunction, they display a variety of wacky problems? Hope so - would LOVE to find the answer to our situation.

How is your hot start issue doing today? Do you still have your wife's MAF on your truck, or did you clean and put yours back in?

 

Yesterday my hot start was gone. I have my cleaned MAF sensor in. My lean code has stayed gone also.

 

Yay!! This is great news for you, and hopefully might mean some good news in my future too! Thanks for keeping me updated!

And congrats on smacking that damn hot start down to hell where it belongs!

 

The throttle plate does not close completely that keeps it from jamming in the bore. If it closes all the way it will stick and you can feel it when you press the pedal it will make the truck lurch from a stand still.

 

Seems entirely logical. Thank you for enlightening me!

 

The throttle stop sets the closed position of the throttle plate (10 degree angle) to keep it from jamming. The "throttle opener" on the rear of the t-body keeps the plate open a tad more via a little spring tension when the engine is off. This allows some additional air flow during starting. As soon as the engine starts and vacuum develops the "throttle opener" allows (overcomes the spring) the plate to close against its stop at the normal idle position.
A bit more can be found in post #1839 in the Lovemytacolots thread.

 

sub'd

Great information here...

 

Update: my idle is now either 750 or about 825, depending on the mood of the beast. I may not replace the IAC valve. I know it'll idle around 650 with a good one on it, but the FSM says 700±50 is acceptable. Besides, it may come down a little more given time to adjust and magic to fix it.

 

Hey there OP!

How's the hot start issue?

Sounds like your idle is doing better, very cool!

 

100% better on the hot start!

 

Hurray! Glad for you and hopeful for me! Just dropped off my donor MAF and told my mechanic about your situation. Fingers crossed.

 

Good luck!

 

Just for the sake of completeness I figured I'd update my maintenance check list. Today I:
-flushed the coolant
-changed all 4 drivetrain oils
-replaced my t-body gasket with a TRD (old one was shot)
-got appropriately sized bolts for the t-body (the long spacer bolts were still in there)
-greased all my slips and youies
-replaced the freaking squeaky clutch spring with a 4 cylinder linear spring (best 4 dollars I ever spent)

No drivetrain shock now, but there is a very minor hesitation like I described in an earlier post. I think it may be normal, I think I'm too used to driving an LS2 GTO and a well cared for 5.3 Sierra. Regardless, I get awesome mileage and my truck runs like a raped ape when I mash the go pedal. I guess I can't ask for much more. Thanks for a good truck, Toyota.

 

FWIW, my hot start issue wound up being dripping fuel injectors, even though they were passing on injector testing machines. Replaced all 6 with brand new (not rebuilt/reman'd) Toyota OEM injectors, fires right up now! Also replaced a crapton of other stuff along the way as well, before a dealer tech finally figured this out for us about the injectors. Good luck to fellow Taco fans!