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Old 04-06-2001, 08:47 AM
Q Q is offline
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Join Date: Aug 2000
Posts: 839
Well, after reading about all of the posts concerning the subject, I thought I would give it a try.

For those who don't know, if you have a car that occasionally jumps from normal idle to an unusually high idle speed (1700 RPM for me), it is more than likely the Idle Speed Control Module in the middle of the firewall. The solder joints become broken and corroded (cold solder joint). I had a mechanic install a manual slide valve.

The repair is quite simple.

Buy a cheap soldering iron and the smallest amount of solder you can get.
Locate the module. It is a black box about the size of a ham sandwich (mmmmm).
There is only one nut holding it on.
To remove the inner circuit board, insert a flat screwdriver into the slots on the bottom side where the connector attaches. Work your way around until you can get the two parts of the shell seperated.
Use care in not touching the circuits on the board or any of the pins of the connect while you are working with it to prevent damaging the unit with static.
Get your soldering iron hot and tin (prime) the tip with a little bit of fresh solder.
Touch the tip of the soldering iron to each solder joint on the board and then apply the smallest amount of solder to re-wet the joint. BE QUICK! Too much heat can damage the components. If it doesn't melt immediately, take the iron off the joint, let it cool down and try a differnt angle or re-tin the iron's tip. The solder on the board should melt almost immediately. Otherwise, you are not getting a good thermal connection between the iron and the joint. This is where most people mess things up. More heat is not better. I can't stress this enough.
Once all of the joints have been flowed with fresh solder, you can put the module back together.
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