In our experience, glow plug problems typically are caused, at least in part, by a failure in this harness. OEM part number 1807648C94. This is the original style glow plug harness for the 7.3L International engine as used in International trucks. This harness should fit early trucks that have the glow plug relay mounted on the rear of the intake manifold. THIS WILL NOT FIT A Ford truck with an International engine. Made in the USA.
Because there have been some cases where this does not fit, the best thing to do is to remove your harness, take a good picture of it and e-mail it to us before you purchase it, so we can be 100% certain that it is exact.
The harness is built using the most common configuration. We have provided a detailed top of engine photograph so that you can compare it to your specific engine.