Where does the modulator valve on the transmission get its vacuum from? Took off the tube at modulator and got no reading on my tester vacuum gauge. Does vacuum come from the injector pump under intake manifold located under crossover pipe? Thanks.

You need the vacuum diagram for your car. Vacuum comes from the vacuum pump on the front of the motor

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There's a vacuum control valve on the IP and a vacuum amplifier at right front under/next to the air filter. You probably have a hose missing or loose if you have no vacuum at the modulator. Harsh shifts, maybe?

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"Buster" in the '95

Our all-Diesel family
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