I have a 94 loyale (EA82) that I picked up a couple weeks ago. 4wd worked when I test drove it. Went to use it last night, and.....nothing. the switch feels like its is engaging, but the drive lines dont, the lights dont come on and it stays in FWD

 

I recently did a light tune up, (filter, plugs, etc)

 

Where should I start with troubleshooting?

Do the heater controls still work? If so, go to step 2.

 

Step 1. Check the vacuum supply. A vacuum line comes off the engine on the passenger side and goes to a white canister at the firewall, where it goes to the heater controls and 4WD solenoid valves. MAke sure it is connected, no leaks or cracked hoses.

 

Step 2. Check where the vacuum line goes to the solenoid valves on the driver side near the firewall, behind the strut. Check the supply is connected to the solenoids, make sure the output from the valves goes to the transmission, make sure the electrical connectors are connected to the valves. Test the solenoids by hitting the switch, they should click.

 

Step 3. Make sure the vacuum lines to the actuator on the transmission are still connected.

 

Might be electrical, check fuses if the solenoids don't click when you push the button.

 

Good luck.

 

Rob.

Rob. THANK YOU!!!!!!!!!!!! You rock.

 

There was a vacuum line that had come loose when I changed the fuel filter.

 

Fixed.!!!!!!!!!!!!!!!!!!!!!