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C-6 shifting

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Old 12-08-2007, 06:51 PM
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knash0727
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C-6 shifting

When I am driving and im am heavy on the throttle my tranny will not shift from 1st to second till it almost redlines. Is this normal? Also when I am driving and it is in 2nd it wont shift to 3rd unless i rev it high and let off or stay on the throttle hard. What could be wrong if there is anything wrong.
 
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Old 12-08-2007, 06:55 PM
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The simplest thing that it could be is a vacuum leak in one of the lines going down to the passenger side of the tranny to the modulator. These lines originate at the throttle linkage where there is a variable vacuum control for the tranny.

Low system vacuum can cause this too. If you have low vacuum, then your brakes may seem a little stiff. If this is the problem, you still could have a vacuum hose leaking somewhere, or your belt driven vacuum pump could be weak.

And we had a poster the other day that found his vacuum modulator on the tranny was bad.
 
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Old 12-08-2007, 10:08 PM
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My brakes actually seem soft. When I push them I have to push the pedal about an inch or so before they actually start stopping. If I press to far the wheels lock up and the skids.
 
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Old 12-08-2007, 11:34 PM
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check the vac suction, all the lines from the vac pump to the injection pump valve, and the lines to the transmission.

You should also check the remaining lines in the vac system as some control things under the dash.

There should be heavy suction at closed throttle and little suction at wide open throttle.
 




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