rosspulliam wrote:
If it just happened like that then it's possible the plugs just got jarred loose during all of the other repairs. I've had both UVCHs (Under Valve Cover Harnesses) in my truck, but the rough running was progressive and could be detected with a Cylinder Contribution Test.
There is no code for "valve cover gasket" but if that entire bank of injectors suddenly quit firing properly and all of the even numbered injectors are failing a buzz test and/or cylinder contribution test that is a very likely culprit.
"The head gaskets were checked" could put the mechanic in the vicinity of the UVCH plugs. They do become brittle with age and perhaps they got broke, disconnected, or something along those lines.
The left side is the easier of the two, I can do mine start to finish in an hour or so.
To expand on that there is a know issue with the UVCH in that year 7.3L coming loose because of it's design. This can be hard to diagnose (remember my warning in my previous post about mechanics being aware of all the nuiances in the 7.3L engine and this is one along with several other like the infamous tranny mechanical diode, coast clutch failure, etc., etc.). Some of these are easy to fix while others are more expensive, but it takes a well trained and highly compentent mechanic well versed in this engine to not be a "throw parts" repairman. IH came out with a $5 or $10 fix that consisted of a special retainer clip for the plugs IIRC for the under cover connection along with a new complete gasket and harness with the improved clips. This issue can start out as an intermittent miss, and progress to it going away as the engine warms up and the connection problem goes away and then slowly progressing to a no start issue. I had this happen to my 2001 Van a couple of years ago and decided to just replace both UVCH gaskets (the new ones have the redesigned retainer clip).
Larry
