Confirming that my ISC is bad

[talontsi01]

I've been having rough idling, stalling and choppy acceleration for a few days now. I am also getting an electric-scraping type sound upon shut off and turning the key to "on". I located the sound and it sounded like it was coming from the ISC. I confirmed this because while my car was shutting off, the sound started, then I unplugged the sensor and the sound ceased. I tried this one more time to confirm.

Therefore, I followed this how to on how to check my ISC: http://dmtalon.v8eaters.com/ISC.html
I found that all my resistance between pins 3 and 4 is 0. All other readings between the pins gave me around 28.

One more thing, my car is running very, very rich (beyond normal dsm richness).


All of these things have led me to conclude that my ISC is bad. I'm looking for someone who had similar symptoms and can say for sure that it is my ISC. Also, to those of you who have been through it, where is the cheapest place to get one? I would rather buy one online, oppossed to a junkyard.

Thanks, Jim

 

[JCMDSM]

The best place I've found is ebay. You can get them for $30-50. Before you buy be sure that you are buying the correct one because the design changed after the 91 I believe. If you can't find one there try the classifieds here or www.dsmtrader.com. Best of luck on your repair!!

 

[titogs95]

You know what, I just found a solution that woked out in my car. I had an idle problem and was the Fuel pump. I was running mad rich. I just installed a Aeromotive FPR and it is way to smoth that I miss my rough idle. It is to weird!!!!!!
The richness maybe the cause of your problem. Because I changed the ISC 3 times and didn't work!
Oh well it is so nice having idle at 900 RPM now I have to get rid of the freaking Rathle!

later.

 

[steve]

I found that all my resistance between pins 3 and 4 is 0. All other readings between the pins gave me around 28.

Between 3 and 4? Are you sure? Pins 3 and 4 are on different coils.

If it's 2 and 3 or 4 and 5, the ISC is bad. Unfortunately the coil would be shorted so you'll need to have your ECU checked to see if you have blown one of the ISC drivers.

Steve

 

[talontsi01]

Wow, very good catch. I didn't even notice that those two pins aren't supposed to have resistance. I guess it's something else.

Like I said before, this scraping type noise I'm getting happens when I turn the key to the "on" position and right after I shut off the car. The noise happens for about 2 seconds, but seldomly longer (about 5 seconds). I had someone turn off the car while I heard this noise. I quickly pulled out the ICS sensor and the noise dissappeared. Does this sound like the ECU, or something else?

Thanks Steve.