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absurdly high idle!

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Old Mar 29, 2012 | 07:48 AM
  #16  
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We're not going to be able to see your Gmail attachments. They need to be hosted somewhere else or attached directly to your post.

Testing the throttle position sensor is quick and easy if you are familiar with a multimeter. This link shows how to test it. Between the PDF and the poster's instructions you can put together how to check the sensor. I don't own feeler gauges so I just rigged it by making sure the idle switch triggered at zero throttle.

I wouldn't completely remove the idle screw. Its purpose is to make sure the shock of the throttle slamming closed isn't borne by the plate itself.

You can't break anything by removing the ISC and cleaning it. It's all metal construction and it's pretty simple to clean and lube if needed.

Finally, remove your ECU and check its capacitors. If they're blown you're just chasing a ghost trying to fix problems that may not exist. Without a healthy ECU you can't troubleshoot anything else.
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Old Mar 29, 2012 | 07:17 PM
  #17  
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Is your throttle cable adjusted too tight?
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Old Mar 29, 2012 | 11:04 PM
  #18  
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Originally Posted by durtysc300
Is your throttle cable adjusted too tight?
how do yo adjust it?


also i have a NEW problem now when i start the car it literally TAKES off now even when im in P or N it just stays in drive or whatever. when the car is off i can switch it to neutral and P but when the car is on it is in D. i havent even messed with anything under the hood yet i just drove it and this happened. so now im guessing that it is the ECU if i were to replace it what year do i need? 92-95?

i feel like such a sucker i picked this car up last week and the only problem it even had was the steering bushing. odometer read 119k 1992 with really nice paint for it's age the interior is imaculate the AC blows ice cold. some minor electrical stuff on the interior like stock CD player wont work but tape and radio work cieling light doesent work .. i guess thats it it even has some really expensive nice, expensive 16" bbs wheels i really want to keep this car but i just blew all my money on this car after saving up and being car-less for 5 months
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Old Mar 29, 2012 | 11:05 PM
  #19  
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here is another try at the pic. somone told me (not a toyota lexus person at all) that there is supposed to be something that plugs in to that black peice in the center of the pic to the left of the TPS

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Old Mar 30, 2012 | 07:54 AM
  #20  
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Buying a used ECU is no guarantee. You could get one with just as many problems or more than your current one.

I had mine fixed by http://www.foreignecurepair.com/

There are other places. There are cheaper places. These were nearby (FL) and have a good reputation and I had zero issues.

If you want us to see your pics, you will have to use the Go Advanced button to compose and attach a pic directly from your computer.
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Old Mar 30, 2012 | 08:07 AM
  #21  
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Looking at the throttle there will be two 12mm nuts. Loosen them both slightly and let the throttle cable have some slack
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Old Apr 1, 2012 | 09:24 PM
  #22  
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update the other day when i went to put it into park it would not go into park it just stayed in drive when i cut the car off it goes into park/nuetral reverse but when i start the car up it imediently puts itself in drive even with the shifter in D and then it starts tring to TAKE OFF.

i spoke with the dealer that i bought the car from and they said to bring it to them and they will fix it so going to take it to them tomarrow and hope for the best. wish me luck
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Old Apr 3, 2012 | 07:47 PM
  #23  
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took it back to where i bought it from they promised they will fix it i'l keep you posted on what they did to make it drive right
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Old Apr 11, 2012 | 04:05 AM
  #24  
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so looks like a lot of it has to do with my IAC motor after watching this video looks like i have all of the symptoms: 2.5-4k idle, idle dropping by a lot when i turn AC on, im going to clean it off ASAP and pray to god it works

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Old Apr 11, 2012 | 01:43 PM
  #25  
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damnit so i went to pull my IAC out and the skrew on the bottom was pitted so i couldent use a skrewdriver. the car dealership i bought it from said that they had to fire thier mechanic but if i paid for a diagnostic somewhere else they would pay for any parts i need so guess i need to do that anyways seeing as who knows how long it wil take for them to geta new mechanic. and wether they pull through on thier promise of fixing my car or not im stuck with the car anyways. going to take it to the dealership next week to get a full shakedown of the car so i know what im getting myself into from the begining
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Old Apr 11, 2012 | 07:01 PM
  #26  
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sounds like a vac leak. Get carb cleaner and spray vac. lines and if its leaking the engine will bogg
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Old May 1, 2012 | 11:53 PM
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bump for new update
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Old May 2, 2012 | 09:06 AM
  #28  
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Definitely an iacv problem.
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Old May 2, 2012 | 11:58 AM
  #29  
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so if the iac was stuck wouldent it stay at whatever idle it was at when i unplugged the MAF sensor?

the idle jumps up as soon as i plug in the MAF sensor wether it is in the housing or not
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Old May 2, 2012 | 01:48 PM
  #30  
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High idle is not caused by MAF sensor. The reason why it jump because computer is reading what the Maf sensor is giving out. Its a load sensor, when u disconnect it, its able to perform what it should, as to calculate air flow. Wheb u plug it back in the pcm recognizes the signal that the Maf is giving, now its able to calculate the air flow again.
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