Shut off then hard to start

[cev65]

I have a '03 7.3 and while driving down the road it occasionally act like it misfires just like its not geting no fuel. Just recently it has been shutting off completely and i have to crank the crap out of it to get it to start. Could someone point me in a direction to start??

[NoRalPh]

Do you have a spare CPS to try? (they'll do that to ya, die while running down the road but, will often restart after a rest)

Is the tank @1/4 full or lower when this happens?

After it dies, listen for the fuel pump to be running when you first roll-on the key (under the truck, below the drivers seat, against the inner framerail).

When's the last time the filter was changed? Does it seem to be happening more on the highway or at higher rpm than going slowly down the road?

Ever see it set the SES light? Could there be codes to direct you?

[cev65]

Whats a cps?? Fuel filter changed not lone ago. Dosnt matter how much fuel. No codes being thrown. Happens more at lower speeds.

[carolinaboy02powerstroke]

Camshaft position sensor.

Stop by ford and pick one up. It's good to carry a spare. Lay on the ground under the front towards the passenger side and it'll be on the front of the block. It takes about 5 minutes to replace it.

Welcome to guzzle's CPS R&R Web Page<

[cev65]

That makes sense. but one small problem. I had some troube with this truck before and people said it was the cps, so when i went to change it the bolt is siezed in the block. I am scared of breaking it off.

[carolinaboy02powerstroke]

Did you try some pb blaster or other penetrating fluid?

If not. Hit it once or twice a day for several days.

You may be able to get the engine warm and then have an easier time breaking the bolt loose.

[cev65]

Ok. i have tried the pb blaster in the past, but no progress. Ill keep it up though. Thanks

[carolinaboy02powerstroke]

Try tightening it some too and then loosening it.

[wireman116]

While you are trying to crank it & its spinning does your tachometer needle move? If your tachometer needle doesnt move its probably like carolinaboy02 siad. your Cam positioning sensor. Just thought this might help you out.

[NoRalPh]

Originally Posted by wireman116

While you are trying to crank it & its spinning does your tachometer needle move? If your tachometer needle doesnt move its probably like carolinaboy02 siad. your Cam positioning sensor. Just thought this might help you out.

Unfortunately, that Test is no longer valid on an '03.

Sometime during the '01 run a major electrical revision was done (if the truck has a digital OD and a Trans Temp Gauge in the cluster, it got the upgrade). Since then, the tach is Not driven directly by the CPS, so it doesn't tell you anything about it's function...