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Old 03-16-2010, 11:18 AM
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Originally Posted by Torque454
Guess my next step is to replace the booster and maybe the modulator. The vac hose is new and hooked up on both ends. I just did it the other day when I was reinstalling the engine and all.
Yeah, I agree. Booster first, you need it anyway. But if you want to work on the tranny problem first, just block off the hose going to the booster so there's no vacuum leak when you hit the brakes.

Then see if by chance that changes the no-shift condition.

If it doesn't, you can pull the modulator from the tranny, and using a piece of vacuum tubing hooked to a vacuum source on the engine (engine running, obviously- you are using the engine as a "vacuum pump"), hook the modulator up to the tubing and see if it retracts. You can also do this by mouth.

And if it does retract, see then if it will hold a vacuum by bending the tubing like a garden hose when you shut the water off, or by putting your tongue over the end of the tubing in your mouth.

It should hold a vacuum as long as YOU do- there should be zero leak-down. And as mentioned before- there should be no ATF in the line or the port of the modulator.

If that all checks out, the next move is to pop the wire bail off the governor cover and pry it off to get a look at the governor. It will just pull straight out.

If the gear's damaged- you will see it. Keep it CLEAN- no dirt or dust, etc.
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