I tried monkeying around with the truck but it got a bit late tonight for me to see outside in the dark.

I was having a heck of a time trying to pull off the 9-wire harness that leads into the valve cover. It appears as if there is a latch on the top of it that needs to be pried open, which I attempted, but the harness still would not give. Rather than break the latch, I decided to give it a rest for tonight and post here.

I searched here and other forums for a photograph of the harness and the latching mechanism, but could not find anything that illustrated how to get the harness to disengage.

Any advice or photos on this?

Secondly:

Before my truck went in for the HPOP/IPR and injector service, it never threw a glowplug related code, and as I mentioned earlier, the shop claimed to have tested the glowplugs when the valve covers were off of the motor.

What is the likelihood that when the shop re-installed the valve covers, that something went awry with the connection to/from the UVCH harness, and to the actual glow plugs themselves?

I am thinking that the reason they are trying to brush this whole issue under the rug and claim that there is no problem, is that they fear that they may not have put it back together correctly, and that there is a loose connection somewhere under the valve cover.

Furthermore, when my wife took the truck back to the shop for them to "scan" the motor, they claimed that there couldn't possibly be a problem, because they never touched any of the wiring associated with the glowplugs. To me, this seems to be patently false, because if they replaced the o-rings on all eight injectors, they would have to had to remove the valve covers and disconnected the UVCH harness from both sides.