Vaccum Modulator Valve

[T_Aggie03]

I know the VMV has something to do with the tranny but I am not exactly sure what. Can anyone let me know how I would go about locating the VMV and how to diagnose it for failure? I know it is located next to the tranny and along side the cat. converters but I have no idea what it looks like. The reason I am even intersted in finding the VMV is because I have reason to suspect that it has caused my Overdrive to fail. Any help would be greatly appreciated.

 

[mdrut]

It is on the side of the tranny, about the middle, round thing that looks something like a hat....It has a rubber vacuum line running into it. USUALLY, when the diaphram blows, it will draw tranny fluid into that line. When you pull the line off the modulator, if there is any fluid in the line at ALL, it is bad. When replacing, be careful, not sure about your tranny, but most have a rod that moves with the diaphram, easy to drop and lose..
What it does, controls shift points.
How Tough to replace?? Not normally a big job, most press in, then have a retaining collar and 1 bolt.
Good Luck.

 

[T_Aggie03]

mdrut, thanks for the help. I will be sure to look at it.

 

[T_Aggie03]

Could a bad VMV cause my Overdrive to stop working? Also, will the VMV make a "pop" noise when it goes out? This is what happened to me when my overdrive stopped working. Just dont know if the pop was the VMV. Thanks.