95 Jimmy 4x4 doesnt work also heat selector switch will not work

[Sparky240]

I have a 95 Jimmy that needs some help. I have a 3 button push 4 wheel drive if i'm driving and hit the 4 hi button the light goes to 4 high but no power to front wheels. When i try to use the 4 lo I hear something and still no power to the front wheels . I took the battery out and that diaphram under neath seems to not show any tear.. Also with my heat i cannot select where I want the air to come out of it just comes out the vent and the floor ? If anyone could help me narrow this down so I could fix it and drive in the snow.. Thanks

[djd99]

Check all your vacuum lines going to and from the ball under your hood and also from the switch mounted on the firewall to your actuator. I had a problem with my 4x4 not working and also ac would not function and it ended up being a vacuum line coming from the ball to the switch had a hole rubbed in it. Replaced the line and all is well now.

[Sparky240]

do u know if the one on the firewall is on the inside of the jimmy or in the engine compartment? I have tried to follow them all and I Belive I have frond the problem just cant find where it goes. I have one line off the vacume that goes between the engine and the firewall and it just pulled right up not connected to anything. I belive that to be my problem. I just can seem to see the other end that it slipped out of

[Sparky240]

help please

[JaVeRo]

If you look on top of the transfer case above the front driveshaft you will find a rubber connector with three vacuum lines. Follow these lines forward over the transmission. On my 2001 (3 button) one of the lines is a vent that is tied to the transmission dipstick. One goes to the vacuum actuator below the battery, you have to remove the battery and tray to find it. And one comes up near the transmission dipstick, goes across the firewall within two inches of the distributor, over the brake booster to a T fitting. One leg of this T has a 2 inch hose connected to another T fitting that looks like it also has a check valve. One leg of this checkvalve goes to the intake.

James

[djd99]

Originally Posted by JaVeRo

If you look on top of the transfer case above the front driveshaft you will find a rubber connector with three vacuum lines. Follow these lines forward over the transmission. On my 2001 (3 button) one of the lines is a vent that is tied to the transmission dipstick. One goes to the vacuum actuator below the battery, you have to remove the battery and tray to find it. And one comes up near the transmission dipstick, goes across the firewall within two inches of the distributor, over the brake booster to a T fitting. One leg of this T has a 2 inch hose connected to another T fitting that looks like it also has a check valve. One leg of this checkvalve goes to the intake.

James

Check all of these vacuum lines over well because most likely you will find a hole in one of these lines. Also check your vacuum resovoir for cracks witch is either a ball mounted on the hood or in my 2000 blazer it's mounted on the drivers side fender.

[Sparky240]

I see all of them They seem to be fine.. I have taken the battery off and the vac. deal under that seems to be all ok.. when I start tracing the vac lines coming from the plastic ball that is on the hood I have one that drops between the fire wall and the engine well that is my problem because its not connected to anything.. I cant find the other end that it goes to. I had my harm in the whole area trying to find a valve or a nother peace of vac line that wasnt attacthed.. dont know if it is suppose to go into the dash to control the heat seletor.. I look for a diagram of my vac lines on the net but no luck if anyone has that year and is willing to take a glance to see were that vac line goes that would be great. It is the vac line that runs over to the engine and goes between the firewall and the engine dont know where it goes from there its is long enough to the bottom of the engine

thanks Jake

[Sparky240]

Originally Posted by JaVeRo

If you look on top of the transfer case above the front driveshaft you will find a rubber connector with three vacuum lines. Follow these lines forward over the transmission. On my 2001 (3 button) one of the lines is a vent that is tied to the transmission dipstick. One goes to the vacuum actuator below the battery, you have to remove the battery and tray to find it. And one comes up near the transmission dipstick, goes across the firewall within two inches of the distributor, over the brake booster to a T fitting. One leg of this T has a 2 inch hose connected to another T fitting that looks like it also has a check valve. One leg of this checkvalve goes to the intake.

James

I will check the one that goes across the firewall within two inches of the distributor.. thanks this will narrow some of them out...
Thanks again
Jake

[JaVeRo]

I don't know how much difference there is between a 95 and a 2001 but this may help
This is between the driver side fender and the brake booster. There are two T's, the line going to the left from the top T goes to the intake on the motor. The line going to the left from the bottom T goes by the distributor and down to the transfer case. The two lines going to the right and down I am guessing are for the AC controls and the EVAP system. If there is a leak anywhere in the system then it is possible there is not enough vacuum for any of it to work.

James

[Sparky240]

Thanks for your guys help.. The problem was the vacuum line that wasn't connected on the back side of the engine

[triparound68]

Originally Posted by Sparky240

help please

there are little electric motors on the heating system on is on the left side and the other is on the top .these control the doors for heat and location. not sure which one controls what. you have to remove the dash to replace the one on the top. its a real pain to change