glow plug question.

littleredstroker · Nov 2, 2011

is there a way to test the glow plugs without pulling them out? and if they need replaced is there a brand i should go with? or are they all kinda the same.. ive heard stories of plugs falling apart and going through the turbine wheel and dont really want to do that just to save some $.

JDub · Nov 2, 2011

littleredstroker said:
is there a way to test the glow plugs without pulling them out? and if they need replaced is there a brand i should go with? or are they all kinda the same.. ive heard stories of plugs falling apart and going through the turbine wheel and dont really want to do that just to save some $.

You can disconnect the valve cover harness and test them at the connector without ever pulling the valve covers. The glow plug wires are the two outer most wires on each end of the connector. And we prefer using only Bosch or Motorcraft plugs. Seen problems with the cheaper Autolite and alike plugs, tips swelling and breaking, threading issues, etc...

Bobby@cp · Nov 2, 2011

When your ready for new glowplugs or relay........

7.3 glowplug package

littleredstroker · Nov 2, 2011

but im not sure if the plugs are bad, I could see how you could test to make sure you have power but how do you know that the plug itself is working? or am I missng the bus?

SDS97_7.3 · Nov 2, 2011

Here you go.

The ohms value for any given pin (plug) should be between (.1) and ( 6) ohms. If you are getting a higher or open line (OL) reading you may have a bad glow plug. With higher values than 6 ohms or OL values you definitely have concern for opening up the valve cover/s and investigating further. Remember if you are testing the engine hot you will get a slightly higher resistance reading than you will when the engine is warm.

4cstr · Nov 2, 2011

Here is a very simple method to determine if there is even power getting to them. When its darker outside, open your door so the dome light is on. Key on the truck. If the dome light dims...power is getting to them. And trust me...the dimming will be noticeable. Granted this method doesn't tell you WHICH glowplug is going bad, but it does let you know if power is getting through the relay to the glowplugs.