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Discussion Starter #1
Hey guy, with this quarantine i finally got time time to throw my motor in the supra. It starts up with no hesitation and holds idle perfectly but it seems as if there is no throttle response. If i press the accelerator pedal nothing happens. Heres a video of what happens.
 

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Hey guy, with this quarantine i finally got time time to throw my motor in the supra. It starts up with no hesitation and holds idle perfectly but it seems as if there is no throttle response. If i press the accelerator pedal nothing happens. Heres a video of what happens.
Seems like a bad cps sensor or throttle body is just bad
 

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I already replaced the cps and what do you mean by throttle body? You mean the tps?
Well based on your video your having no response of the engine getting more air as if the throttle plate is stuck closed or your tps doesnt see that it is open you can try disconnecting the tps and see if it changes when you rev it or try cleaning out the throttle body it get very dirty in the back make sure the throttle body as a whole is functioning properly
 

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Discussion Starter #5
Well based on your video your having no response of the engine getting more air as if the throttle plate is stuck closed or your tps doesnt see that it is open you can try disconnecting the tps and see if it changes when you rev it or try cleaning out the throttle body it get very dirty in the back make sure the throttle body as a whole is functioning properly
I know the throttle plate it self opens and the tps is fine as well becauee theres a difference in rpms adjusting it. As for the video you might not bw able to hear it but it seems as if it wants to rev but somethings holding it back.
 

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I know the throttle plate it self opens and the tps is fine as well becauee theres a difference in rpms adjusting it. As for the video you might not bw able to hear it but it seems as if it wants to rev but somethings holding it back.
Strange when i had a similar issue i would rev the car but it wouldnt go past 2k so i disconnected the tps and it was normal i replaced it and everything was okay the only 2 things that sounds like tht would be the afm which i doubt or tps which has to be adjusted sometimes with replacement it could also be lack of fuel delivery
 

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Have you checked timing and verified with a timing light gun and locked it in by jumping the two pins (TE1 and E1) on the check connector? Also I would check for a vacuum leaks. Maybe one your intake pipe is loose or AFM.

Sent from my LM-V350 using Tapatalk
 

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TPS, or AFM isn't sending out the signal to the ECU to increase fuel supply.
Instructions for checking both are in the Toyota Service & Repair Manual. (TSRM)
Since you have your air filter off, reach inside the AFM, and push the flapper open.
It should flood the engine almost instantly by telling the ECU to send more fuel.
If it doesn't, your issue could be there.
Or if you can't open it, that is your problem, it's stuck.
Check the electrical connection.
The workings can be inspected by using an Xacto knife to carefully cut the silicone sealer holding the black plastic cap on.
See if had gotten full of water somehow (have seen it before), and corroded the contacts, or the wiper that slides over them as the flapper swings open.
Also readjust the TPS per instructions in the TSRM.

On another thought, did you accidentally leave a rag in the intake manifold ?
Seen that before also.

If there is something else wrong with EFI system, you could be just running off the cold start injector, which means if the engine comes up to temp, the engine will die when the cold start injector shuts off.

Good luck, and keep us informed.
 

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Discussion Starter #9
So today i woke up and started the car and the idle would just jump to 4000 then drop jump and again and drop. After a while it holds a steady idle and i can rev it but then it cuts out if im try to hold rev.
 

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Discussion Starter #10
Have you checked timing and verified with a timing light gun and locked it in by jumping the two pins (TE1 and E1) on the check connector? Also I would check for a vacuum leaks. Maybe one your intake pipe is loose or AFM.

Sent from my LM-V350 using Tapatalk
Im gonna try redoing this today thanks.
 

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Discussion Starter #11
Just for anyone that does want to know. The tps wasn't placed on correctly. Even though that was fixed the car has a jumping idle I cant figure out.
 

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I would check the Mass airflow sensor. On mine, before I changed it, If I revved the engine and removed my foot from the gas, the car would just stall as it came down. Made for interesting driving around corners with a clutch.

I used a multi-meter to check and sure enough mine was toast. I found a new one on eBay. Instant difference and no problems since.
 

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Just for anyone that does want to know. The tps wasn't placed on correctly. Even though that was fixed the car has a jumping idle I cant figure out.
I had a similar issue where my car would not rev past 1500rpm. There was an issue with the position of the throttle position sensor. You can see on the tps that there are screws you can loosen then this enables you to twist it clockwise or anti clkwse.

to properly calibrate the tps you have to connect a voltmeter/multi-meter to it. When connected you turn it gently and wait for the resistance to hit infinity or unity, this is the position you want to tighten the screws at and fix in the tps.

You may or may not know that there are good trouble shooting guides within the TSRM manuals - they just take a while to read and get your head into, but worth working through them for peace of mind.

Good luck
 
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