I replaced the relay (with the 86 6.9 version for $19.99 thanks to the threads on this forum). The relay is now clicking. When I have the front two glow plugs on the driver side connected, the relay stays on. When I connect any of the other 6 glow plugs, it immediately cycles.

Does this mean that those 6 glow plugs are likely bad? They all passed the test light test (hooking the test light to the positive side of the battery and touching them).

Is my controller likely good?

The WTSL still does nothing. I put the test light on the WTSL connector on the controller and got nothing when I turn the key on. Is this supposed to put out 12 volts or should I connect the multi-meter and look for a lower voltage?

I also tested the connectivity (using the OHM setting on my multi-meter) of each glow plug wire and I have it, i.e. no breaks in the wires.

Thanks,

Jason