I have a 1997 F350 Powerstroke. Was driving home the first day after I bought it when I started to experience loss of power and rough running. Finally limped it home. Bought a new crankshaft position sensor hoping that was the problem. It was not. Had a couple friends come over to help troubleshoot the problem. We found that the entire left side was not firing at all. We haven't pulled the valve cover off yet to inspect the wiring inside. Any suggestions on why else the left side wouldn't be firing or how I should proceed to find the problem. I don't have a scanner. I am trying to fix it myself. My wife wasn't real keen on my buying the truck to begin with, so I would like to keep the cost down on repairs, to keep her happy. Also can anyone recommend a good shop manual to buy for this truck? If the wiring harness is the problem, can I buy it anywhere or only from a Ford Dealer?

 

can't help with the firing of inj.
try
www.helminc.com for the manual

 

It may be as simple as the wiring harness coming unplugged from the IDM on that side of the engine. Pretty quick to look at. The harness enters at the base of the valve cover. If anything looks fishy go ahead and pull the cover the gaskets are re-useable. Another pretty common one is for the clips that hold the harness plugs into the individual injectors to fail.

The wires that go to the GP's/Inj pass through the valvecover gasket. These connectors have been known to give trouble in higher mileage trucks. Look for burnt or discolored looking connections.

Hope this helps,
DG

 

I would bet money that it is a bad connector at the valve cover. Simple enough to fix, with about $50 worth of parts. There are two connectors to the valve cover gasket on each side. There are five pins in each connector. The two outside pins (1 & 5) are for the glow plugs, and the next two pins in from each side (2 & 4) are each for one injector. The center pin (3) is the ground for the two injector pins.

Ohm pins 2 & 4 to earth ground (any good connection on the engine). Any continuity at all is a sign of a problem. These pins should only show continuity to each other or pin 3.

Pins 1 and 5 should show very low resistance, (2-5 ohms) to earth ground if the glow plugs are good. The problem is always caused by too much resistance in the valve cover connector pin when the glow plugs cycle on, which leads to overheating of the connections. This melts the surrounding plastic, etc, until one of the injector wires is exposed and potentially shorted to ground. Once the resitance is out of specs the IDM will shut down an entire bank of cylinders to protect itself.

Not hard to fix on a truck (PITA on a van though). Probably need a new valve cover gasket for about $40 - $50 and at least one new injector wiring harness. You might also consider installing a GPR bypass switch or relay to reduce the frequency and lenth of time the glow plugs are powered, which will greatly reduce or even eliminate the problem.

 

Good info MDB. I had not considered the effect of the glow plugs on this rather delicate connection point. I disabled my GPs yesterday until cool weather returns...

 

That sounds exactly like my problem, you don't live anywhere near Northern Michigan do you? Thanks for the info, I do have a truck and not a van so it should be easier!
Ted

 

No, northern Indiana, which is too far north as it is