First post. Anyone know how much voltage should be at the glow plugs when the key is turned on. I get 9 volts at the glow plug connector. Does the voltage drop as it goes through the controller? I put my voltmeter negative lead securely on the neg side of the battery and the positive lead solidly on the glow plug connector. I just put in new ac delco plugs, haven't heard anything about the ac delco's. Brand new batteries, interstate 850 cca's. Thanks in advance fro your replies.

 

when the glow plugs are hooked up they draw a crapload of power. so the reading you get with a good plug hooked up and the reading you get with no plugs hooked up will be different. but if the controller is working properly, it should deliver battery voltage to the glow plugs.

and the AC Delco glow plugs are a crap shoot. they may work, or they may burn out after the first application.
these glow plug systems were designed for using Motorcraft/Beru glow plugs.

 

First, check the Battery Current. Next, the Current at the Relay should be within 0.5 DCV. Next, energize the Glow Plugs - The Voltage on both sides to ground should be within 0.5 DCV. 9 DCV is not bad. Have you load tested the Batteries and Cleaned the Cables?