valve cover removal, uvch problem?

[jeffintwin]

Hey everyone, I'm obviously new here. We've recently had a problem with a 96 f350 7.3 powerstroke. The thing is idling very rough and seems to have all the power of a leafblower, engine vibration is pretty bad, especially at low RPM, possibly one or more cylinders not firing. We started off by replacing the fuel filter, but to no avail. The truck has been having this problem on and off, but was usable. Now the problem won't stop. Based on the reading I've done, it seems the logical place to start may be the connections of the uvch inside and outside of the valve covers. Maybe I don't know where to look, can someone point me to a guide for removing those valve covers? Am I way off here? Should I be starting somewhere else? Any help is greatly appreciated.
Thanks.

[sea71]

Cant help you , but some one who can will chime in shortly. WELCOME to the site too!

[Tyler]

Can you post a video of it running? Does it sound a lot louder than normal? It could be injectors going down the tubes. How many miles?

[jeffintwin]

I cannot post a video of it running...at least until tomorrow. It has roughly 189k miles on it. Yeah, it seems abnormally loud, kinda like when you start it really cold x10

[Farmy22]

Its hard to tell when your not there to hear/see it but i belive you are headed in the right direction. The valve covers are fairly easy, just remove the bolts and pop them off. The right bank is a little difficult to get off but it will come. Unplug the connectors inside and outside the gaskets and check them out. Start with the simple stuff first, sometimes the smallest thing gives you the biggest problems. Forum searches help a lot too, gives you ideas on what to check next.

If you want to try it and dont have anyway to check codes just unplug the uvch connector on the valve cover gasket. There are 2 on each gasket. Look at the pins and see if there are any melted. What happens is the glow plugs start to go out and the resistance builds so much heat it melts the harnesses and or connectors.

[Jarrod B]

keep us posted on this testing

[jeffintwin]

I didn't figure it could be all that difficult to remove them. I don't have a whole lot of mechanical experience though. I kinda learn as I go along . At the risk of being thrown out of the forums completley, the bulk of my experience has been with a 66 chevy truck and a 92 GM with a quad4. This powerstroke is our work truck, so we are hoping to fix it soon. I've seen about half a dozen other things that could be the problem as well. These include camshaft position sensor, high pressure oil pump, injectors, and another larger wiring harness, even possibly a fuel pump, I suppose. It just seemed like after the fuel filter the next cheapest and easiest thing to do was to check the uvch (also, this seems to be a chronic problem with the 7.3?). I'm trying to research injector testing now.

[Farmy22]

Originally Posted by Jon

If you want to try it and dont have anyway to check codes just unplug the uvch connector on the valve cover gasket. There are 2 on each gasket. Look at the pins and see if there are any melted. What happens is the glow plugs start to go out and the resistance builds so much heat it melts the harnesses and or connectors.

That last part is very true, when mine melted down it was the connectors that coincided with the bad glow plugs i pulled out at the same time. So theres another thing to do if you do end up with the covers off. They are pricey but saves some time down the road.

I have fixed about 3 7.3s including mine with this same problem. All with close to the same symptoms as yours. mine was intermittent at first too, this was before i knew about forum help so i chased it for a couple days before i found the problem.

[jeffintwin]

Thanks everyone. I'll let you know how it goes tomorrow.