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idle adjustment?

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Old Feb 24, 2010 | 04:23 AM
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Default idle adjustment?

I was wondering if there is a way to adjust the idle on the tC through a bolt. I have done this on some
older cars I was just wanting to know if it is possible on the tC and if where is the location of the bolt?

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Old Feb 24, 2010 | 04:47 AM
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Absolutely not. the tC is drive by wire and is thus the throttle body is controlled through an actuator and is
controlled through the idle control module which is not adjustable, not even through a Toyota dealership.

You're thinking of the older style drive by cable set-up that you could adjust the idler screw.

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Old Feb 24, 2010 | 05:03 AM
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thanks for the help
Old Feb 24, 2010 | 06:16 AM
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why do you ask? are you having some sort of idling problems?
Old Feb 24, 2010 | 02:32 PM
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i put poly motor mounts in my car and it idles a bit rough. so i was going to try to bump it up about a 100rpm to get rid of the majority of the vibration.
Old Feb 24, 2010 | 05:22 PM
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i have poly motor mounts. didn't really cause that bad of an increase in vibrations at idle.
Old Feb 24, 2010 | 08:44 PM
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Originally Posted by oueng
i put poly motor mounts in my car and it idles a bit rough. so i was going to try to bump it up about a 100rpm to get rid of the majority of the vibration.

I hear you on that one!! I was gonna do the same. Can the F/IC make this possible?
Old Feb 24, 2010 | 08:47 PM
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i was told it could. But i wanted to see if i could do it with out dropping the money for a fic
Old Feb 24, 2010 | 11:21 PM
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fic can not increase idle
Old Feb 25, 2010 | 02:27 AM
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yeah, nothing can really increase idle. even a stand-alone engine management can't do it because the throttle body is still controlled by the throttle control module. if you really wanted to, you could drill a tiny hole in your thottle plate to bump up the idle.
Old Feb 25, 2010 | 03:14 AM
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ohh ok. so i guess i am just going to have to deal with the rough idle. Thanks for all your help guys
Old Jul 27, 2015 | 10:44 PM
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So there is no way to adjust the idle then. Well that sucks cuz my car when I put in the clutch and the rpm's drop they drop all the way to zero and the car dies. As long as I keep the rpm's up then I'm good. How do I fix that issue?
Old Jul 28, 2015 | 06:05 AM
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Originally Posted by Desp7397
So there is no way to adjust the idle then. Well that sucks cuz my car when I put in the clutch and the rpm's drop they drop all the way to zero and the car dies. As long as I keep the rpm's up then I'm good. How do I fix that issue?
couple of things can cause this.. dirty throttle body, dirty MAF sensor.. I've had the throttle body gummed up before that caused the car to stall. Get some MAF sensor cleaner, clean the MAF sensor and use the cleaner to clean the throttle body/plate. That should fix the stalling issue, also replace your spark plugs if they're close to 90-100k miles old. NGK part 4589 is what is stock, no need to try anything else.. factory works well.
Old Jul 28, 2015 | 02:18 PM
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Ok cool thanks. I'll try that. The maf sensor is what is plugged in by the air filter right? Where is the throttle body located?
Old Feb 2, 2021 | 04:18 PM
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Default I found the fix to the low idling

Originally Posted by cburglb34
fic can not increase idle
the gas pedal is where the problem is at.. with time the plate will bend out of factory specifications.. just bend the plate towards the right of the car to bend back to factory position.. if necessary placing a rubber stomp behind where the pedal meets the end will raise the lever to where car will idle at x1000 rpm.. i placed a rubber washer about 4cm thick. And my idle is near x1000 which gave the car life.. no more shaking, no more rough shaking when AC is turned on.. brakes return to feel new as the low rpm made the brake sink to the bottem since no pressure was building up..

conclusion of the matter toyota used very thin metal plates that will bend out of factory position.. causing lower rpms

car feels great by the way.. smooth red lights 🤩🤩🤩🤩🤩🤩🤩🤩🤩..
Old Jul 7, 2021 | 09:55 PM
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Originally Posted by jeffsciontc2008beast
the gas pedal is where the problem is at.. with time the plate will bend out of factory specifications.. just bend the plate towards the right of the car to bend back to factory position.. if necessary placing a rubber stomp behind where the pedal meets the end will raise the lever to where car will idle at x1000 rpm.. i placed a rubber washer about 4cm thick. And my idle is near x1000 which gave the car life.. no more shaking, no more rough shaking when AC is turned on.. brakes return to feel new as the low rpm made the brake sink to the bottem since no pressure was building up..

conclusion of the matter toyota used very thin metal plates that will bend out of factory position.. causing lower rpms

car feels great by the way.. smooth red lights 🤩🤩🤩🤩🤩🤩🤩🤩🤩..
I'm extremely curious about this. If this works on my '08 after all these years and 230k+ miles I'll report back for sure. This nearly meets my symptoms, except it's so bad that if I slowly press the gas from idle (very slowly) the car will gently stall. After doing all the usual cleaning, I've been pretty stumped. Ran it by a few buddies and one suggested I start with the pedal itself - now I read this gem of a post haha
Old Aug 7, 2021 | 05:29 PM
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Originally Posted by jeffsciontc2008beast
the gas pedal is where the problem is at.. with time the plate will bend out of factory specifications.. just bend the plate towards the right of the car to bend back to factory position.. if necessary placing a rubber stomp behind where the pedal meets the end will raise the lever to where car will idle at x1000 rpm.. i placed a rubber washer about 4cm thick. And my idle is near x1000 which gave the car life.. no more shaking, no more rough shaking when AC is turned on.. brakes return to feel new as the low rpm made the brake sink to the bottem since no pressure was building up..

conclusion of the matter toyota used very thin metal plates that will bend out of factory position.. causing lower rpms

car feels great by the way.. smooth red lights 🤩🤩🤩🤩🤩🤩🤩🤩🤩..

could you please confirm that this mod is still working?

doesn’t the system just re-learn the new position of the pedal?

or does it work until the negative battery is disconnect? After which you would have to remove the mod, wait till the system learns the pedal position and after it is done learning then do the mod all over again...??
Old Aug 12, 2021 | 02:33 PM
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Originally Posted by Entellerin
I'm extremely curious about this. If this works on my '08 after all these years and 230k+ miles I'll report back for sure. This nearly meets my symptoms, except it's so bad that if I slowly press the gas from idle (very slowly) the car will gently stall. After doing all the usual cleaning, I've been pretty stumped. Ran it by a few buddies and one suggested I start with the pedal itself - now I read this gem of a post haha

have you tried this pedal mod? Have you gotten it to work? I tried it and for me it seem to work except after a while the system compensate and I’m back to square one with too low of idle...
Old Aug 12, 2021 | 03:01 PM
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Originally Posted by Salzamani
have you tried this pedal mod? Have you gotten it to work? I tried it and for me it seem to work except after a while the system compensate and I’m back to square one with too low of idle...
Sorry it took so long to get back to you. I'm new to this forum, so I've still got to set out time to set it up correctly. In fact, yes, I tried this, and by the time I got home, the ECU had rendered my idle back roughly to where it had been before, albeit a little better. The TPS (Throttle Position Sensor, attached to your Throttle Body) and the Pedal Position Sensor (the one on the gas pedal) are all simply trying to meet their desired targets. However, I believe that my issue, at least, is in my pedal position sensor. To be clear, when I removed the gas pedal (two 10mm bolts and 1 connector for those interested) I placed a small fiber washer behind the black, plastic stop point. The "bending metal plate" thing seemed unnecessary, since there are 2 nuts (I think they were 8mm? Maybe 7mm?) that attached the pedal position sensor to the pedal, with room for adjustment. I started the car with the gas pedal plugged in, held the brakes firmly and pulled the handbrake, then shifted into drive and made my adjustments through the sensor position. Next step: New position sensor, with the same adjustments. This time I'll try without a 12V reset and see where it gets me. I'll be honest though, no matter what I do, I strongly believe the AC is still going to be the bane of our idle.
Old Aug 12, 2021 | 04:49 PM
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Originally Posted by Entellerin
Sorry it took so long to get back to you. I'm new to this forum, so I've still got to set out time to set it up correctly. In fact, yes, I tried this, and by the time I got home, the ECU had rendered my idle back roughly to where it had been before, albeit a little better. The TPS (Throttle Position Sensor, attached to your Throttle Body) and the Pedal Position Sensor (the one on the gas pedal) are all simply trying to meet their desired targets. However, I believe that my issue, at least, is in my pedal position sensor. To be clear, when I removed the gas pedal (two 10mm bolts and 1 connector for those interested) I placed a small fiber washer behind the black, plastic stop point. The "bending metal plate" thing seemed unnecessary, since there are 2 nuts (I think they were 8mm? Maybe 7mm?) that attached the pedal position sensor to the pedal, with room for adjustment. I started the car with the gas pedal plugged in, held the brakes firmly and pulled the handbrake, then shifted into drive and made my adjustments through the sensor position. Next step: New position sensor, with the same adjustments. This time I'll try without a 12V reset and see where it gets me. I'll be honest though, no matter what I do, I strongly believe the AC is still going to be the bane of our idle.
thank you for the response Entellerin. Very well described. Yes I’m with you. I also found that any adjustment made by putting a spacer on top of the pedal stopper although seemed to be affecting the idle only seemed to change the idle temporarily as the system compensated after a short drive, always back to square one.

With that in mind any pedal position adjustment we make whether adding a spacer on the stopper or the pedal position sensor would always be compensated for as well after a short drive. Wouldn’t you agree with that?

just to clarify when you say “Next step: New position sensor”. I’m assuming you’re referring to the throttle position sensor that is on the throttle body right? if so wouldn't you agree that any adjustment made to that would also not hold permanently and the system will just compensate after a drive?

what do you think about the idea about drilling a small hole into the throttle plate it self? Doesn’t that technique work as far as raising the idle? Keeping in mind that we have a drive by wire throttle bodies. Can anyone that knows the answer chime in on this?

just trying to raise the idle permanently to around 1k so that running the AC doesn’t feel like the car is going to shake me to death...
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