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Discussion Starter #1
Checked my ISC and O2 sensor with a different meter, and they both read zero resisitance. It therefore appears that they're both fried. Funny bx besides the rough idle, my Talon runs great and pulls hard. Should run better after I change the sensors. Anyone please correct me if I'm wrong. (Like if I had to grant permission to be corrected around here, hehe.)
 

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Well, since I've been granted permission ;)

Neither one will make a bit of difference on how the car pulls, it might even run better since it will be rich. The bad ISC will screw up the idle. I guess you already know that. Gas mileage will suffer.
 

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I'm wondering what you mean by a zero reading, are we talking volts or ohms? Also, I had to point out recently that an open circuit is not zero ohms. Zero ohms is at the other end of the scale.

On the four wire O2 sensor our cars use two of the connections are for the electric sensor heater. A reading of infinite ohms across these connections means that the heater has burnt out. At the other two connections the sensor should develop a voltage between zero and 1 volt with the car running and warmed up. This should swing towards 1 volt if you suddenly open the throttle.

The ISC has four coils. These are wound with thin wire insulated with varnish. The resistance (ohms) through a normal coil should be in the 30 ohms range. If the varnish fails the coil can short internally. This will produce a lower than normal reading. If the coil is open the reading should be infinity.
 

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Discussion Starter #6
Barney, your correct. Zero is not iffinity, its at the other end of the scale.
The reading I'm getting for all isc coils = zero ohms, not iffinity.
The reading I'm getting for pins 3-4 on the O2 sensor (the electric sensor heater) = zero ohms, not iffinity.
I haven't gotten a voltage reading for the other 2 connections on the O2 sensor.

So is it possible for all the ISC coils to read zero ohms?
 

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No, that's not possible. You have a problem with your test equipment or procedure.
 

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vr4gazm said:
Also, wouldnt those sensors throw a cel if they were bad?

MIKe
Castle-1 has a 1g, and other cars may vary, but on a 1g a bad ISC never throws a CE and the O2 sensor only occasionally.
 

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Discussion Starter #10
Finally bought a new digital mutimeter. The 1st ISC coil reads something crazy like 300ohms. The rest read a bit over 30ohms. Hence, I believe it is now safe to say that my ISC is wacked. Correct?
 

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Castle-1 said:
Finally bought a new digital mutimeter. The 1st ISC coil reads something crazy like 300ohms. The rest read a bit over 30ohms. Hence, I believe it is now safe to say that my ISC is wacked. Correct?
Yup - aren't dead parts fun?

ISC is an expensive little POS to replace, too... mine was $200 from Conicelli...
 
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