Problems - Hope you can help!

[lms]

My name is Luke, and I have a 1994 F350 Powerstroke with a ZF 5sp. I am working in Iowa, but alas my truck is sitting in my driveway in Minnesota because I can't get it started. Before it wouldn't start, it had been running poorly due to the EBPV malfunctioning (hissing and simultaneous power loss) and lord knows what else. In fact, shortly before it wouldn't start, it seemed to have lost a cylinder as well. The next time I go home I would really like to tear into it and get its issues resolved.

Now for the questions:

I believe that the first step to solving my truck's issues is to determine the no start cause. I assume the fastest and easiest way to do this would be through a diagnostic scan tool. From the research that I have done thus far, I have concluded that the 1994 model year's pcm is not OBD II compatible. Is this correct? If this is correct, is it true that you (PHP) can "reflash" '94 pcms to make them work with OBD II scan tools such as AE's tool? How much would it cost to "reflash" my pcm to a '96 or '97 pcm?

Also, once I get my truck running again, I would like to buy a pheonix chip as well. Simply loading a stock tune in the chip would not be the same as "reflashing" and it would not allow me to interface with a scan tool correct? I ask because of this were correct, I could skip sending in my pcm to be reflashed and simply buy the chip.

If you can think of any other comments or paths to point me down please share them.

Thanks for the help!

Luke

[ChuckD]

On the no start is your tach moving while your cranking. What is the temp outside? CPS, GPR, glow plugs like to go out on the OBS. Low batteries, even though they may seem fine, you may not be getting the 140-150 rpms required to start. Check the UVCH, they are will known for coming loose and causing a "lost a cylinder" condition.

[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?

[Power Hungry]

To answer one of the original questions, yes... we can reflash the 94 PCM with the 97 program to allow for proper OBDII Scantool functions. If this is what you'd like to do, we can certainly get you taken care of.

As to the rest, the guys have covered about everything you can check without a scantool.

Best of luck!

[ChuckD]

I replaced my positive cable today with a larger one. I can say for sure that mine spins quicker and starts faster. The older your cables get they can get corroded, that increases the resistance thus lowering the voltage which will cause the starter to spin slower. I got mine locally for $100 and as said before its alot bigger. I had to work to get it in the battery to battery groove. If you want one let me know.

[ChuckD]

Here is some pics.