Vacuum modulator on tranny goes bad?
10-03-2001, 01:21 PM
#1
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Vacuum modulator on tranny goes bad?
What are some of the symptoms you fellow members know of when the vacuum modulator on the transmission goes bad?
Having problems and trying to determine the cause! :rolleyes:
Thanks!
Having problems and trying to determine the cause! :rolleyes:
Thanks!
10-03-2001, 01:32 PM
#2
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Re: Vacuum modulator on tranny goes bad? (Vader953)
Symptoms are faulty/poor shifting, but your problem may not be the modulator. I've read material to the effect that modulators seldom fail but get blamed for a lot of poor shift troubles. Technically, if the modulator is not physically damaged or is not leaking, it ought to be okay. Check carefully for leaks. There is an o-ring in there which might go bad and result in a leak without the modulator being bad.
Check the vacuum line to the modulator. A leaking connection will result in poor shifting.
Check the vacuum fitting on the manifold. It may look good, but could still be leaking at the base. Not only will you get poor shifting, but all the vaccum accessories will suffer and overall performance will be off.
Check transmission fluid level.
If all these seem to be okay, you may want to consider rebuilding the tranny.
Check the vacuum line to the modulator. A leaking connection will result in poor shifting.
Check the vacuum fitting on the manifold. It may look good, but could still be leaking at the base. Not only will you get poor shifting, but all the vaccum accessories will suffer and overall performance will be off.
Check transmission fluid level.
If all these seem to be okay, you may want to consider rebuilding the tranny.
10-03-2001, 01:47 PM
#3
Safety Car
Re: Vacuum modulator on tranny goes bad? (Vader953)
Sometimes a modulator diapram breaks and the engine sucks up transmission fluid and makes your car smoke.
Check the line from the modulator to the intake or carb and see if its wet at the connection near the motor hook up.
Check the line from the modulator to the intake or carb and see if its wet at the connection near the motor hook up.
10-03-2001, 02:35 PM
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Re: Vacuum modulator on tranny goes bad? (Tim H)
Had this happen on a 68 Ford Torino one time - Vacuum hose came off on the modulator and car would not shift into 3rd gear unless I got the rpms up to about 4 or 5000. Put car up on rack reinstalled vacuum hose, car started shifting properly again.
10-03-2001, 03:52 PM
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Re: Vacuum modulator on tranny goes bad? (Vader953)
Lots of smoke on the highway not bad in the city.On the highway you will lots like a stunt plane at a air show,Pull your #8 plug if its oily thats it,east fix 1 bolt that holds a clamp cost for and ajustable one is in th 15-20 range :crazy:
