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BTW - Duty Solenoid C can be on without it "burning" out. It's very similar to the one they put in the 4EAT trannys on the AWD XT6's, I've owned a few of those and never had an issue with those solenoids.

 

Follow the vacuum leak advice. Buy a can of ether, spray around the vacuum hoses where there could be a leak, see if the idle changes. This is caused by a leak sucking ether into the engine.

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The Duty solienoid C get a pulse width modulated signal (PWM) from the tranny ECU that ranges on the SVX and XT6 from 95% to 5% at a relativly high frequency. This has the effect to finely position the hydrolic valve it actuates. At 5% PWM the valve is closed and no fluid is dumped from the transfer clutch and you get the bind up. With 50% PWM some fluid is dumped (partialy open) and you get partial pressure on the transfer cltuch and at a 95% PWM signal you get no pressure on the transfer clutch and no power transfer. So while your driving down the road you can almost bet the solinoid is basically "ON" (4EAT). The solenoid moves quickly when the tranny ECU detects a slip, but they are not constanly opening and shutting at the frequency of the PWM signal.

These solenoids by design are always powered in the 4EAT and I have yet to see a single coil go bad. I have seen two valve seats go bad. I've seen transfer clutches go bad, but never the coil. These things use very little power, and generate little heat. You damage nothing by overriding the valve either way.

In my rally car I installed an adjustable PWM to control my Duty Solinoid C. I can easily adjust the power transfer to the rear with it.

 

So to the person with the issue: does the issue go away in FWD mode? If it doesn't torque bind is not your issue.

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The Duty solienoid C get a pulse width modulated signal (PWM) from the tranny ECU that ranges on the SVX and XT6 from 95% to 5% at a relativly high frequency. This has the effect to finely position the hydrolic valve it actuates. At 5% PWM the valve is closed and no fluid is dumped from the transfer clutch and you get the bind up. With 50% PWM some fluid is dumped (partialy open) and you get partial pressure on the transfer cltuch and at a 95% PWM signal you get no pressure on the transfer clutch and no power transfer. So while your driving down the road you can almost bet the solinoid is basically "ON" (4EAT). The solenoid moves quickly when the tranny ECU detects a slip, but they are not constanly opening and shutting at the frequency of the PWM signal.

These solenoids by design are always powered in the 4EAT and I have yet to see a single coil go bad. I have seen two valve seats go bad. I've seen transfer clutches go bad, but never the coil. These things use very little power, and generate little heat. You damage nothing by overriding the valve either way.

In my rally car I installed an adjustable PWM to control my Duty Solinoid C. I can easily adjust the power transfer to the rear with it.

 

So to the person with the issue: does the issue go away in FWD mode? If it doesn't torque bind is not your issue.

 

Mr Radon:

 

Thanks for your help.

I will try the FWD mode as soon as the coming snow storm passes. :eek:

 

~Howard

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Just an update:

 

Here in Philadelphia we are in the midst of another "blizzard". The 2nd part of the storm is expected later tonight and ending early Friday with 6" - 12" more inches for this snowy season. :eek:

 

I haven't switched to FWD yet but I'm waiting for the storm to pass. The problem is now starting from the time the car starts rather than driving for at least 1/2 hr. When it does it's shaking at idle, it feels more like someone has hit you from behind rather than coming from the front. :confused:

 

Early on when I had just purchased this vehicle my mechanic discovered an old Penna state inspection sticker which indicated about 20K more mileage than what I had purchased it. We were both confused how you could roll a digital odometer and we both thought it was just an error. But now I believe it wasn't an error and instead of having 77K on this Forester I have 97K. :mad: This would explain things like why I had to replace all of the struts this past fall.

 

~Howard

:banana:

Edited by howards11
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Hey Guys I am new to this site. But I had the same problem with my 2000 Forester and all it turned out to be was Spark plugs needed toi be changed and the air flow from the pod filter was a bit blocked.

 

It might help, it might not. The blocked air flow caused the forester to backfire and shudder at idle.

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