High idle

[daneyan]

hey guys my supra is idling kinda high, when i start it up it idles at about 1500rpm. i thought it was just warming up, but it only drops to like 1250 to 1300 rpm after warm up. could it be my ISC or vacuum leak or can i just turn down the adjusting screw?

 

[T701jz]

From the way you describe it, it sounds like you could just back down on that screw and go from there. High idle is normal at start as long it comes down where you set it at when it gets warm up. Also not a bad idea to start checking all your vacuum hoses b/c when you have a leak it tends to idle higher.

 

[shaeff]

hey guys my supra is idling kinda high, when i start it up it idles at about 1500rpm. i thought it was just warming up, but it only drops to like 1250 to 1300 rpm after warm up. could it be my ISC or vacuum leak or can i just turn down the adjusting screw?

dont touch the screw. if you have an idling problem, it's either a vacuum/boost leak, TPS, ISC, bad plugs/plug wires/ coilpacks.

dont touch that screw. it wont do anything. when you move it the ECU will just compensate for how much you moved it.

check your codes. use the link in my sig. then get back to us.

-shaeff

 

[MDCmotorsports]

What shaeff said to a degree... just don't touch the screw. IT will adjust the idle, but it will be an adjustment you regret.

Sounds like you have a vacuum leak, low coolant level, or your timing has come undone.

 

[supraman7mgte]

best way to check the ISC valve is to let the car warm up,and turn off the ignition. With the hood up,listen at the ISC valve for a sequence of 4 "ticking" sounds coming from it. That would be the setepper motor in it working properly. If not,time to replace it!

 

[GrimJack]

Even if you get the 4 clicks, there is a very good chance that it's still all gummed up inside. Take it out and clean it off, 15 years of PCV blowby isn't good for moving parts.

 

[daneyan]

thanks for all the info guys, i wish i could have someone come check it out so i can compare cars, cause the guy i bought the car from has most of the vacuum line off with screws in them. i'd really like to know where they go so i was wondering if there's anyone round my area with an mkIII turbo? i'm in pompano beach FL. i will check the codes as u instructed shaeff and check back with u. oh and where is the isc valve located?

 

[IHI-RHC7]

It is located in between the intake manifold and the valvecover at the frontmost part of engine.

That' snot the most clear picture, but hopefully it helps.
-Jake

 

[supraman7mgte]

the ISC is located on the intake manifold,just ahead of the throttle body. it has one multi pin connector going to it,and a hose. also there are 2 water lines going to it,the top bolt is easy to get out,the BOTTOM one is kinda tricky,suggest using a extension w/ a swivel joint. once removed,as per Grim,just clean the hell out of it! CARB CLEANER,SIMPLE GREEN,JUST GET ALL THE OLD CARBON OUT OF IT dam caps lock

 

[Jspec7m88]

i had the same problem when i first got the car...from past experience w/ the 3000gt...i didn't mess with the screw, i just started checkin hoses...turned out there was a small leak...my idle was almost EXACTLY like yours...since i replaced the hose...cold start up, idles at about 1200 for a couple seconds then sits right at 1000. check the hoses!

 

[daneyan]

thanks again for help guys. i will check on the isc tomorrow and clean it out. also what's and easy way to see if i have a leak in one of my hoses? are there any simple tests or would i have to examine every hose?

 

[Eric_Odie]

my car idles at 2100!!! hahahaha hella bad, but i don't drive my car that much anymore, cant afford the gas, and i have some things i have to fix, so while doing the process of fixing i'm going to look at all hoses! i getting new accordian hose, and bypass valve hoses, those had cracks, got turbo to intercooler piping cause those had cracks, and yeah we'll see if that's it!

 

[shaeff]

my car idles at 2100!!! but i don't drive my car that much anymore, cant afford the gas

hmm.

-shaeff