Quadtrac Trouble shoot

[Fornesto]

I'm doubting that my Q-trac is working correctly. Of the three vacuum lines on the g-box switch, which should have vacuum pressure to them under normal operating conditions? Any idea what that pressure should be?

[g503]

there are many answers, do a search ,it was answered just a while ago lots of info

[Santa Claus]

The center port should have manifold vacuum to it. Depends what mode you are in as to which port will have vacuum, one will be E Drive and the other will be normal. Hope this helps.

[joe]

Yeah as Santa said the center hose goes to the vac reservoir and should have vac to it at all times when running.

[letank]

best guess would be at least 5 to 7 of vacuum, more is better..... connect a vacuum gauge at the QT case and see how much is your reading.. and if it is holding pressure

if you have a leak between the vacuum reservoir and the QTswitch... like for the heater control.... you will have low vaccuum... so you can disconnect the heater splice and use the vacuum gauge, vaccum pump combination to find the bad section

either a bad hose(s) switch in the glove box... or leaky TC actuator.... in that order

the first 2 are easy fix... the last one you need to pull the QT cover to remove the e clips that hold the actuator.... BJ sells those

a quick way is too connect a source of vacuum to the actuator....

at least on the 79 you have the metal lines...not all rubber from firewall to the QT

Michel