runing without isc?

[DeeBo]

well im pertty sure my isc is dead ### when i unpluged and reset the ecu it the surge stoped and isnt ideling high.... but when i rev high while driving and push in the clutch my rpms drop to 0 and it dies? sooooooo im asking what might be my problem and is it a good idea to run without the isc?

 

[brute]

I'd say just go to a junkyard and pull one off. I got a working one for like $10.

Oh, and buy more than one. I bought 2 and one didn't work when I put it on. The second one I tried fixed the problem.

 

[B0OST]

I wish i knew about some junk yards around where i live .

 

[DeeBo]

I'd say just go to a junkyard and pull one off. I got a working one for like $10.

Oh, and buy more than one. I bought 2 and one didn't work when I put it on. The second one I tried fixed the problem.

i live in the middel of no where alaska...... trust me i would of done this if i lived anywhere els ....... so is it safe tho? car is runing alottttt better with out it just wondering tho

 

[steve]

It's not safe if your engine dies while your driving.

Dead ISCs is a common problem. You need to measure the resistance of the coils on the bad ISC to see if it has damaged the ECU. Coils shorted to the power pins blow the drivers on the ECU.

http://dmtalon.v8eaters.com/ISC.html
http://www.stealth316.com/2-isc-iac.htm

About 25% of the ECUs I repair have blown ISC drivers that aren't burnt up. You can only tell that they're bad by testing them. Part of the problem is due to a ISC circuit running under one of the capacitors that leaks. When it leaks the trace can short to 12v or ground. Toss a coin as to which. Both disable the ISC but like shorts in the coils, shorts in the circuit to 12v blows the driver.

Steve

 

[VapedTalon]

Steve by any chance does the isc circuit run under this capacitor?

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[Auto RS T]

Steve by any chance does the isc circuit run under this capacitor?

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My old ecu had visible damage in this area also. I am also intersted in what was damaged.

 

[steve]

Steve by any chance does the isc circuit run under this capacitor?

Yep, there is a via for one of the ISC control circuits right under C106. Not the best routing choice when you have defective capacitor seals.

Steve

 

[VapedTalon]

Since you know your way around the Ecu's in our cars I will throw this out there. Is it posible for capacitor C106 to leak and cause issues with the ISC that lead the Ecu to fiddle with the alternator. I ask this because my alternator is overcharging causing my headlights to pulse and my motor itself to pulse at idle. I have already taken in my alternator to have the voltage regulator checked and it is fine. I have also checked the coils on my ISC and they are all fine(Yet to test with a 6 volt battery though).

 

[steve]

Simple answer is no. The ECU doesn't do anything with the alternator on a 1G besides consume current.

If your voltage regulator is "overcharging" then it by defination it can't be fine. If you lights are pulsing you might have a blown diode. Measure both the DC voltage and the AC voltage.

Steve

 

[VapedTalon]

Well as the whole story goes I had this problem before and I took my alternator in to get checked and it was fine. At the same time I had the battery unplugged so the ecu reset. When I put everything back together it worked perfectly no overcharging, which confused me. It ran perfect until this week when it started doing it again, I guess I'll get another alternator even thought the one on there is less then a year and a half old.