It wasn’t until 4 months later that I read in an online Powerstroke Diesel forum... “Don’t buy the cheaper UVCH’s!” (Under Valve Cover Harness) Well here I am 4 years later taking my valve covers off and now I know why.
Saving a Few Bucks May End Up Costing You More In the Long Run
This wiring harness os very vital to the operation of the 7.3 Powerstroke Diesel. It received the electrical signals send from the computer to tell the injectors and glow plugs when to operate. (Glow plugs pre-heat the cylinder for proper combustion of diesel fuel - Diesel engines don’t have spark plugs) So when I noticed my truck missing or studdering, I knew I had something going on. I had a couple injectors that weren’t firing. Immediately I think the worst of course, then I gather my thoughts and start diagnosing the issue as I am driving down the road.
After finding an awesome wiring harness checking procedure online I found out the issue. When you are dealing with plugs that have 42 wires in them... ummmm ya... the internet is a lovely thing. Lol. Honestly I would have to say that I lucked out on this one. The main harness going from the computer to the plug on the valve cover checked out perfect. Having a pinched or chaffed wire would have been an absolute nightmare!!! So I plugged it into the valve cover and did a couple more tests and sure enough, injectors 1 & 3 had a high resistance (ohms) on the wiring. Then I remember... I bought the Dorman brand harness because I could get both of them for $140 including the valve cover gasket. The Ford brand or International brand (The 7.3 Powerstroke is an International designed engine not a Ford designed) were $150 per side!!! Well what would you do in a situation like that??
The injector has a 2 wire plug and the glow plug has a single wire plug. Believe You Me... it’s really tight in there to get these on and off... Good Lord!!
Well, with oil kind of “splashing” around under the valve cover, you want all electrical connections sealed up and clean. The truck didn’t act up until the engine got to operating temp. Therefore the oil was heated up and thinned out allowing it to get all up in there. All the injectors plugs should have been sealed up like this one...
These are the ones that tested bad. Not Good... Not Good at all
Cracking and splitting apart
About 2 hours later the International Brand UVCH was installed and the beast isn’t skipping a beat! It almost feel as though it has a little more power... Nah!! That is just me. Lol.
So learn from my mistakes... Cheaper at the time, may not be cheaper in the long run. Could you imagine if this happened when I was out of town with my camp trailer???!!!!! I am glad it happened now. Lol
Spend the Extra $$ Now
It could cost you more in the future..