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low rpm on idle after replaced CTS

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Old 08-14-2011, 01:09 PM
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pwb
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Default low rpm on idle after replaced CTS

Hi, i replaced my radiator, fan clutch, termostat house, termostat and coolant temperatur sensor today since it runs hot ( it took me 3,5 hour ).
The idle is 200-400 rpm, it used to be 1500 when cold and going down to 800 when hot, but after replaced the CTS its run at 200-400 on idle and somtime even stops. I used a ohm meter and the ohm on the CTS was 285ohm when the temperatur was around 100 celsius, is that to low, are the new sensor bad?
I see some place it should have be arround 600ohm at 100celsius, but some other sites tell me that it should be arround 250-300, what is correct and is it possible to adjust the idle rpm on my GC 1993 4.0L?
Old 08-14-2011, 01:16 PM
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pwb
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could it be that i need to run the car for some time since the battery was disconnected for 3,5 hour? i have only let the engine run at park for 10 min x 2 for fill coolant.
Old 08-15-2011, 02:52 PM
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Hi, i replaced back to the old CTS but that didnt help, but the engine dont increases the rpm if i turn on the A/C, its use to increase the rpm a litle moment before the A/C clutch hit in. Could i have broken some vacuum lines or something, does the idle controls with vacuum? The engine runs fine when i drive it, its only the idle. I have a 1993 and i cant find any vacuum diagram anywhere in my engine.
I have to lines that are disconnected from something, but i dont know what and they have been loose forever i think, i will take a closer look tomorrow. I have the Haynes manual and its seems like one of the vacuum lines is from the gas tank, but where should that go? should it go in to the EVAP canister (3d line?) i can only see two lines going to the EVAP, but there is 3 (or 5?) tubes out from the canister, but on the 3 in the middle its seems like the bottom one is closed and the two other goes to the manifold and air filter box.
The second loose line could connect to something arround the bottom radiator hose, but there isnt anything in that area that it fits in to.

The picture attached is from another evap canister, my isnt looking like this, it have the two on side and the on in the midle and then two more in the midle over the on that is there.
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Last edited by pwb; 08-15-2011 at 03:45 PM.
Old 08-15-2011, 08:35 PM
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Idle air control motor takes a while to reset, that is also what controls the idle when air is on.
Old 08-17-2011, 12:26 AM
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Originally Posted by tiwvr1
Idle air control motor takes a while to reset, that is also what controls the idle when air is on.
After 1 hour of driving the engine still didnt run nice on idle, but after turning it off and waiting a min or two and then starting it againg it was much better, so it is correct that this will take some time and is there some guide on how to drive when learning the car after a reset? The transmission did go very high in rpm before shifting in the beginning, but that also got more normal after a some time.
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