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my 95 deville is having idle problems...i posted a thred about it a few threads down...the isc motor?...can someone tell me exactly what that is...is it a little black box under the hood right next to the throttle...if that is it then that is the problem...because it is suposed to move automaticaly as i hit the gas but it seems to be stuck...and thats y it idles so high....when i turn the car off its supposed to re adjust itself back but it doesnt...it just makes a bunch of grinding noises?...is that the isc motor...how much do they run?
 

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Idle speed control motor is usually very cheap around $30 or so and it controls how much are gets into the engine so if it stalls or wants to then that could be the problem if its stuck open sometimes though it can stay closed causing other problems.

Does it do that when the car is warm or cold or both?

I had a similar problem with another car which would stall at low rpm when changing gears etc. it turned out to be the egr valve was staying open or closing too slowly.

All I did was unplug the egr valve and my problem was solved.

I've read of other temporarily disconnecting the idle speed valve too see if that corrects the problem etc. you can try that

the isc motor is on the throttle body usually close to the TPS the idle motor for your car is actually about $90 it looks like the pic in this post.
 

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dont disconect EGR on the 4.x series engines , it will ping and knock like a sonfabitch , and may result in premature engine damage ...

open the hood , have a helper turnt he key tot he "run" psotion , if the ISC doesnt move out its bad....

Start the engine , note the ISC movment , once again if it doesnt move its bad

shut the engine down , does it reatract ? if not the ISC is bad...

another check is (i had to look this up , my memory is getting rough) :
With the Key in the run position and the engine not running:
Push and hold "off" and "warmer" on the climate controll display
push fan speed to high when you see "PCM?"
push fan speed to low repeadedly till you see "PCM OVERRIDE"
push fan speed to high
push fan speed low repetadly till you see "PS03"
push and hold "warmer" , have your helper watch the ISC for movemnt , it should extend

to retract:
With the Key in the run position and the engine not running:
Push and hold "off" and "warmer" on the climate controll display
push fan speed to high when you see "PCM?"
push fan speed to low repeadedly till you see "PCM OVERRIDE"
push fan speed to high
push fan speed low repetadly till you see "PS03"
push and hold "cooler" , have your helper watch the ISC for movemnt , it should retract


with it fully reracted you can unplug the ISC motor not at the connector at the ISC but the connect on up b y the throttle body , just trace the wires away fromt he ISC , youll see connector two , all youll do is destory and hurt yourself if you mess with the one at the ISC motor , wait till you remove the ISC motor from the car before removeing the connector at the ISC motor ...

you can just disconect the ISC and then adjust the plunger to get a "decent" idle out of it , but be prepard for it to stall on you after say pulling off from highway speeds ...

the ISC is fairly cheap as oc pointed out .....defainately cheaper than a tranny , as if its idleing very high its like brake torqueing the tranny , all that does is build up heat , heat kills these trannys faster than anything ...
 

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Stoneage_Caddy

How can you get injured? also I read your thread, you are missing some steps according to the shop manual, you are suppose to ground the generator... right?
 
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