I've had the same problem with one of my foglights on my 95' Z for about 2 yrs. Most recent it was burned out and I replaced it with a new one for the wonderful price of $9 bucks. Worked great for almost 2 months then started not coming on when I turned on the lights. I get out walk over and give it a swat with my hand and it'll come back on and work just fine until the next time the lights go on, or sometimes last a couple days. I checked all the wiring, bulb firmness when installed(seeing it's not rattling around in there),etc. I can't figure out what the problem is and it's driving me nuts. Eventually it will prematurely go out and once replaced will work great for 2 months and start all over again. Any ideas what my problem is, it's just an inconvenient hassle. Thanks

 

This is almost alway caused by a bad electrical connection or ground. Keep looking!!