YAIT - Yet another idle thread... (1 Viewer)

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CharlieS said:
Do you have anything nice or helpful to add?
Click to expand...

Yeah, undo your modifications and baseline the vehicle. Stop trying to outsmart the Toyota engineers. You think *I'm* not being nice or helpful? Dude, YOU started a second thread about a problem that YOU caused. You want a bunch of people talking about your problems more than you want to solve them. Does that sound like a nice thing to do?

I'm literally telling you the solution to your problem and yet you're crying about me not being helpful.
 
Did you repin the o2s? I always ran the correct ntk o2s with no issues in the manifold. I also had everything removed for emissions and all vacuum lines pulled except for the one u see the tps and one for fuel pressure.
 
gummycarbs said:
Yeah, undo your modifications and baseline the vehicle. Stop trying to outsmart the Toyota engineers. You think *I'm* not being nice or helpful? Dude, YOU started a second thread about a problem that YOU caused. You want a bunch of people talking about your problems more than you want to solve them. Does that sound like a nice thing to do?

I'm literally telling you the solution to your problem and yet you're crying about me not being helpful.
Click to expand...
You are not being helpful. I thought you were funny in the beginning. Now you’re just being an a******.
 
FMC80 said:
Did you repin the o2s? I always ran the correct ntk o2s with no issues in the manifold. I also had everything removed for emissions and all vacuum lines pulled except for the one u see the tps and one for fuel pressure.
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Sorry Charlie, I’m not being helpful either. I just wanted to post what Ajax posted twice to mess with your mind, man. Happy Friday. Sorry to bugger up your thread. That’s weird about your O2 sensors. You should listen to @gummycarbs and undo everyfucking rubber hose and metal clamp to troubleshoot that.
 
No worries. You are being helpful. Have a great weekend!
 
I tested out the O2 sensors, and they were in spec and passed all tests. Note: the 95-97 style (Denso) sensors have a higher resistance spec on the heater circuit than the original 93-94 style (NTK).

I readjusted the TPS and that seems to have smoothed out what little fluctuation was left in the idle.

For anybody that cares, I dialed back the timing a tiny bit since at 10 deg BTDC it had some hesitation off the line when it was cold. I'm closer to 5-6 deg BTDC now and that seems to be a sweet spot.
 
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CharlieS said:
I tested out the O2 sensors, and they were in spec and passed all tests. Note: the 95-97 style (Denso) sensors have a higher resistance spec on the heater circuit than the original 93-94 style (NTK).

I readjusted the TPS and that seems to have smoothed out what little fluctuation was left in the idle.

For anybody that cares, I dialed back the timing a tiny bit since at 10 deg BTDB it had some hesitation off the line when it was cold. I'm closer to 5-6 deg BTDC now and that seems to be a sweet spot.
Click to expand...
I also went 6 deg BTDC and it idles super smooth.

I found my IAC was super touch to adjust but got it.

Maybe your good now? Run her as is and see what happens after a 50 miles or so.

🍻
 
CharlieS said:
I didn't repin the O2 sensors. I read in this thread (https://forum.ih8mud.com/threads/re...-sensors-for-93-94-1fzs.1178425/post-15033791) that they could be used as is with the plug modified to remove the indexing rib. https://forum.ih8mud.com/threads/re...-sensors-for-93-94-1fzs.1178425/post-14092173

That being said, I'm happy to depin and repin/modify if there is a way to verify what the correct pin out is.

I printed the FSM pages for the O2 sensors and will test them this weekend.
Click to expand...
If you click through some of the links on those threads, you will find people having issues with using the denso.
 
CharlieS said:
I didn't repin the O2 sensors. I read in this thread (https://forum.ih8mud.com/threads/re...-sensors-for-93-94-1fzs.1178425/post-15033791) that they could be used as is with the plug modified to remove the indexing rib. https://forum.ih8mud.com/threads/re...-sensors-for-93-94-1fzs.1178425/post-14092173

That being said, I'm happy to depin and repin/modify if there is a way to verify what the correct pin out is.

I printed the FSM pages for the O2 sensors and will test them this weekend.
Click to expand...
Don't repin because I did and it caused me problems.
 
Just circling back to close this out.

The 80 is idling like a dream, and running like a top. There are no more idle issues, no stumbling. Woo hoo!

My ECT sensor was out of spec, so replacing that made a significant difference. I was definitely chasing vacuum leaks for a while, and then put way too many cycles into trying to save my IAC. At the end of the day, the IAC just wasn't doing the job as well as it should and I picked up an Aisan oem part. Replacing the IAC, and then fine tuning the TPS seemed to be the key. Also, fwiw, I dumped two cans of Seafoam into the gas (with the idea that it might be good for my injectors), and don't know if that has been beneficial or not...

I replaced a lot of parts that were long in the tooth (it has just under 300k miles and had a lot of engine bits that seemed like they could have been original), some of which could possibly have been fine for some time. I do a fair number of trips and go off-road places far from parts stores, so reliability is big for me. I don't want to be the guy to ruin everyone's trip with a preventable mechanical failure. So this mechanical baselining was worth it to me.

Thank you to everyone who helped me so much. I don't think I would have solved this without you and your advice and guidance. This is such an amazing community. I started to list out all the people that pitched in, but realized I would definitely miss someone and didn't want to do that. So, I figured it might be better to just thank everyone. :) So thank you all!

The amount of collective knowledge and experience on this board is mind boggling. I am constantly amazed.

Thanks again all.
 
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CharlieS said:
Just circling back to close this out.

The 80 is idling like a dream, and running like a top. There are no more idle issues, no stumbling. Woo hoo!

My ECT sensor was out of spec, so replacing that made a significant difference. I was definitely chasing vacuum leaks for a while, and then put way too many cycles into trying to save my IAC. At the end of the day, the IAC just wasn't doing the job as well as it should and I picked up an Aisan oem part. Replacing the IAC, and then fine tuning the TPS seemed to be the key. Also, fwiw, I dumped two cans of Seafoam into the gas (with the idea that it might be good for my injectors), and don't know if that has been beneficial or not...

I replaced a lot of parts that were long in the tooth (it has just under 300k miles and had a lot of engine bits that seemed like they could have been original), some of which could possibly have been fine for some time. I do a fair number of trips and go off-road places far from parts stores, so reliability is big for me. I don't want to be the guy to ruin everyone's trip with a preventable mechanical failure. So this mechanical baselining was worth it to me.

Thank you to everyone who helped me so much. I don't think I would have solved this without you and your advice and guidance. This is such an amazing community. I started to list out all the people that pitched in, but realized I would definitely miss someone and didn't want to do that. So, I figured it might be better to just thank everyone. :) So thank you all!

The amount of collective knowledge and experience on this board is mind boggling. I am constantly amazed.

Thanks again all.
Click to expand...

Good on you for your detailed description of your efforts.
It's helpful to me and will be for others too.
 
Love following all these threads as no better way to climb the banana curve. I've done stuff I never remotely imagined I could because of MUD and YouTube.

Glad happy idle ending!
 
It’s great to see an end to a troubleshooting thread also!
There are so many threads started and then left open with no resolution.

🍻
 
CharlieS said:
I've been chasing a TOYOOBD tool, but they seem to be no longer available. I'm strictly multimeter and FSM for now.
Click to expand...

I may have found a solution for this. Toyobd app update had made in unusable at this point, at least for me.

Fingers crossed this other option works out.
Waiting on some stuff to arrive so I can test
 
ZackR said:
When you check the TPS also check that the throttle plate closes fully and that there is some slack in the throttle cables (FSM will say how much). If the throttle plate is open slightly (or the throttle body is dirty not allowing it to close) then some air is getting past and the IAC isn't able to fully control the idle.

A scrap piece of vacuum hose and some vice grips are handy to pull the throttle opener back (apply vacuum to hold open and clamp with vice grips). I removed the throttle body during adjustment so I could be sure the throttle plate was all the way closed and everything was easier to access.

View attachment 3411016

When adjusting keep a close eye on the multimeter, it will go from an open circuit to within the expected range as you fine tune it. You really want to be sure its within the specified range when you let go of the throttle plate and the spring closes it.

View attachment 3411025
Click to expand...

My vehicle has no throttle opener (Aussie spec manual trans).

what does applying vacuum to the throttle opener do? Does it change the throttle position?

I attempted to adjust TPS on mine last night. Followed the adjusting steps with a 0.620mm feeler gauge, then verifying adjustment with 0.50mm and 0.75mm, multimeter readings are all over the shop!
TPS resistance test readings are within the specified range.
 
Applying vacuum to the throttle opener allows the throttle plate can close all of the way so the tps can be adjusted from zero opening. The throttle opener keeps the throttle from slamming closed if you let off all the way and when the engine is off it allows the throttle plate to open just a bit.

I'd focus on the multimeter reading over the feeler gauge. You want the signal to the ECU to be correct and it's getting that signal electronically.
 
ZackR said:
Applying vacuum to the throttle opener allows the throttle plate can close all of the way so the tps can be adjusted from zero opening. The throttle opener keeps the throttle from slamming closed if you let off all the way and when the engine is off it allows the throttle plate to open just a bit.

I'd focus on the multimeter reading over the feeler gauge. You want the signal to the ECU to be correct and it's getting that signal electronically.
Click to expand...

Ok, so I've adjusted it with .62mm feeler gauge in the throttle stop.
Positioned the TPS so it's only just triggering a reading with the Meter. If I button it down at that I should be good?

The FSM says to check OHMs with .50mm & .75mm feeler gauges. Readings for these tests doesn't seem to correspond with FSM
 
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