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OBD II Code P1247 ?'s Mfr Cntrl Fuel Air Metering - Ford Truck Enthusiasts Forums

 

Turbo code may be due to inadequate exhaust pressure to drive turbo when you stepped on the throttle. The problem may not be that. Powerstokes are very notorious for throwing other codes when a problem results. The reason is that if one component fails momentarily or keeps failing it throws off other component readings causing them to flag. Going down the road and everything starting to shake at idle and low rpms but smoothingout under high sounds like,,, you are loosing injectors but eratically. Meaning that your harness (underneath valve cover) is blown or the prongs on the harness have burnt. This harness is also the valve cover gasket. The gasket is made with wiring inside it. The mating end to your harness from the ECM plugs into it beneath the valve cover. If the prongs get burned or the wiring on the inside burn into it will send mixed signals to the injectors causing an out of balance condition on the engine. When you raise the rpm it will continue to get less until you reach a higher rpm then it begin to smooth out. This happens because the faster the rpm the closer the firing pulses are and this allows the engine to run smoother at a reduced horsepower. Unfortuantely the only real way you can check this is with a scanner by doing a injector pulse test or pulling the valve cover and doing a visual inspection. if you do one you may as well do the other. Around 100 per side if you do it yourself.

 

Sexton 81,

Try this. With the truck in it's limping configuration (check engine light on, engine loping erratically while running) carefully wiggle the under valve cover harness connection right at the valve cover where the wires enter the valve cover on the side of the engine that's missing (you'll hear it, it's very obvious. The live side clatters, the dead side just makes mechanical noise with no combustion/injector noise). wiggle the harness right where it goes into the valve cover. Wait a split sec and presto, the thing should come back to life. If that's the problem, don't bother just getting the harness without the gasket as the problem is probably the double female in the gasket itself.

while you're in there, examine the large cannon plug (42 pin?) on the drivers side valve cover, the one that rests right on the valve cover. If your engine has a slight miss, chances are one of the injector wires is grounding out on the bottom of that harness to your metal valve cover.

May the force be with you.

 

Hello . I know this post is old, but I am have the same problems with my 7.3 shaking and losing power. when I Checked the code it was also P1247 and P1280 . I was wonder what solved the problem. I really appreciate any help you can give me to take care of this problem. Thanks

 

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Having same problem did u get ur problem fixed??

 

icp sensor did you try what is in this video unplug sensor and see if there is a difference in idle sound. I had very rough idle and took all injectors out to rebuild them. If you hear no change in idle unplugging icp sensor replace the sensor first. Watch video very helpful👍