Engine/Transmission (1994 - 1998) Vacuum problems

[guntruck]

Is there anywhere I can look for good info on where to start with this vacuum leak problem? My 4wd dont work my heater controls dont work and my brake/abs light keeps coming on from time to time very faintly. I know its vacuum I checked down on the axle and there was no vacuum. Do you just have to trace and check? Or is there a better method or certain thingsa you should check first? Thanks.

 

[wcjp]

Pull the vacuum feed line. There's a large line from the vacuum pump to the powerbrake booster. In that large line is a T connection. Disconnect the small vacuum line leaving the T. Hook up a vacuum tool. Start by disconnecting the vacuum line feeding the transfer case. This will probably be located in the middle of the vehicle at the rear of the engine compartment. The vacuum line will drop down and may touch the intake manifold. Plug the open outlet of the threeway or install a straight splice. Continue until you find the problem.



My 96' was leaking at the 4way vacuum boot at the transfer case. DC doesn't sell just the boot. I ended up buying 1/4" vacuum tubes. These are a tight fit into the boot. I then connected vacuum hose from the 1/4" tube to the transfer case. The vacuum hose must be a tight fit on the transfer case. I chose to piece it out instead of removing the boot altogether. I still may remove the boot in the future. The vacuum boot is keyed and will only go on one way. I didn't want to remove anything unless necessary.

 

[Andy Redmond]

You may have vacuum line oil contamination (ck. valve at vaccum pump) search the archives by my name I've posted about the fix for this before.



I like to see 20" of vac at idle at the vac. pump.



The tip on the lines to the transfer case is excellent advice also.



If it just blows out the defrost postion, I bet the actuator above and to the right of the accelerator pedal has a bad diaphram and is leaking vacuum.



Also look at Dodgeram.org for the "recall" for this. .



Good luck

Andy

 

[guntruck]

Thanks guys working on this today, hopefully successful =).