Spark Plug Wire
 

I have a 1992 volvo 940gl and the front spark plug wire keeps coming off the spark plug, what is causing this?

plug wires
 

Your plug connector and or wire connector may be bad. Replace both with Bosch product. Make sure your motor mounts are not failed also.

I have been using Bougicord wiresets that are specific for these Volvos. they are the original spec... nowdays, Bosch is selling a lot of cheap stuff.

Volvo spark plug wire set (740 760 780 940) Bougicord 271483 | FCP Euro

I agree, go with the Bougicord. They are oem and last a very long time.

Would an exhaust leak cause this also?

an exhaust leak cause the spark plug wire to keep coming off? I can't imagine how that would happen, unless it was a really bad leak that blasted directly at that spark plug.

now, exhaust manifold leaks CAN cause excess air to get sucked into the exhaust, causing the O2 sensor to think the car is too lean, so it tries to richen it up, causing bad fuel economy and drivability issues. mostly, exhaust leaks make noise. :D

my motor mounts are fine, its the front spark plug wire that keeps popping off the plug.

its possible, I suppose, that something is funky about the number 1 spark plug, maybe its missing the tip that the wire snaps onto? its far more likely that you need new spark plug wires, and I highly recommend getting bougicord wires as they fit just right and are very high quality. both FCP Euro and IPD USA have them in stock.