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Hello, I am the happy owner of a 1992 seville 4.9 liter. It has 150000 miles on it now and is starting to have some problems. There is a servo type component located near the throttle cable pulley on top of the motor that that has a small rod that comes out when gas is applied and returns when let off. It has developed a tendency to remain partially out causing a high idle. Is this the cruise control module? Can it be disassembled and cleaned or should it be replaced? Also, the service ride control light has started coming on, any ideas? Thanks in advance for any assistance. Jim
 

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It sounds like the servo thing you are talking about is the ISC motor (idle speed control). Check the codes and see what they say. This could be why your SES light is coming on. And if it is the ISC motor, I would replace it. That part should only be around $50 to $80. Good luck!
 

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AKPsiMC03 said:
it could just be REALLY far out of adjustment like mine was.
How did you adjust it? I noticed that if I tapped the rod with a screwdriver it would return to normal idle. When I disconnected the motor the car ceased to run, so that didnt work too well. Thanks! Jim
 

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yea, my 94 sls is going crazy its like if i give it like 1/3 throttle and let off it will stay idled at about 2-3 thousand rpms. I watched it and its the electric motor that controls the idle is just pushing it way in and out, but if i mash the throttle it will idle back down to normal. and also it looks like my throttle cable has quite a lot of slack.
 

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Clean your TB. Remove the air box and duct. Remove the MAF sensor (black tub bolted to the TB with 3 bolts). Then clean the TB bore and throttle plate with carb cleaner, tooth brush and rag, especially where the throttle plate meets the bore.
 

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You beat me too it Ranger, thats what I was going to suggest. I did the same thing a few months back. It appeared as if no one ever did it before. At 60000 miles, you can imagine what it looked like, what the throttle felt like, and what difference this made!

Give it a shot. It's easy and it's one of the best performance boosts I have experienced for my ETC.
 

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well i'll do it tommorow then, considering the motor has 80,000 miles on it and 117000 on the car so who knows how dirty it is. Only thing is it just started doing it after my battery died.
 

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When you open that throttle plate and look in there after 80K you'll be absolutely amazed (and discusted).
 

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ratherbriding99 said:
yep, it was pretty black, but didn't help my idle problem. I did notice im having the same problem that jim is, soo. How do you adjust the servo?
From what you say it doesn't need adjusting...it needs to be replaced. They do not just get out of adjustment. The PCM controls the idle speed control motor to adjust the idle speed to the desired level. The PCM is constantly monitoring engine RPM and various loads and transients and it uses that info to operate the idle speed control motor to keep the idle at the desired level and to prevent stalls and such.

If the idle speed is acting up like you describe it most likely is the closed throttle switch inside the idle speed control motor. IF you hold the throttle open and press the plunger of the ISC motor you can feel a detent or "click". That is the closed throttle switch and if it fails or gets sticky then the idle speed control algorithm in the PCM does not know what to do....

Replace the ISC motor. Lots in the archives if you search using "idle speed control motor" "closed throttle switch" etc....
 
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