My gauges keep failing
My 1967 Mustang has issues with its fuel level, oil pressure and temperature gauges that are powered by a 5-volt resistor behind the instrument panel. The car had an aftermarket 3-gauge set mounted under the dash when I got it, but I wanted to put it back to original. The factory resistor had apparently failed in the past.
I purchased a Scott Drake, solid state improved resistor and installed it. It worked briefly and then quit. The supplier sent me another without question, and it worked for about 5 minutes after cranking the engine, and then the gauges went to zero. I quickly checked the fuel level and oil pressure but never get the engine up to temperature before failure.
The problem is most likely the way you are going about the installation, according to Brandon at Mustang Country in Paramount, California–which is incidentally a good place to purchase parts and get advice on how to install them. But here is the important thing. Before you do anything else disconnect the battery.
After that you can replace the five-volt resistor and hook up the gauges without problems. Only when everything is connected and the gauges are back in the car do you reconnect the battery. If you try to replace the resistor or do any of the work with the battery in the car, you will damage the resistor. I have used Mustang Country for years, and have found them to be knowledgeable and reliable. For another resistor and further information contact them at:
14833Lakewood Blvd. Paramount, CA 90723