Problems - Hope you can help!

[cleatus12r]

There are a few things the 7.3L Powerstroke needs before it will start.

1. Battery voltage to be a minimum of 10.7 volts during crank.
2. High pressure oil at a minimum of 450 PSI during crank.

a. The PCM will not even begin to command injection events without seeing this minimum pressure. If the injection control pressure (ICP) sensor is bad and the PCM never "sees" 450 PSI on this input, it will not command injector action. An easy way to test this is to simply disconnect the sensor. The PCM will then command an injector pulse width that correlates to 725 PSI of ICP. If it still doesn't start, keep looking.

3. Fuel pressure. If there is no fuel pressure, then fuel will not be fed to the injectors. They may be actuated by the PCM but without sufficient fuel, there will be no combustion.

4. Camshaft position sensor (CMP) operation. This sensor is vital to the PCM operation because it's the only input to the PCM for engine speed....which it has to know for nearly every function it performs.


I usually tell people to crank the engine for 8-10 seconds and see if there is any smoke coming out of the exhaust. White smoke signifies either inoperative glow plugs, low fuel pressure, or low compression.

No smoke means that there is no fuel being injected. Either there's no RPM input to the PCM or there is no fuel being injected.

By knowing what your tailpipe is telling you, we can take a direction from there.

What have you got?