98 Expedition multiple problems

[stamp11127]

Look at the problem logically.

In order to run the engine needs 3 things:
1) Air
2) Fuel in the correct amount and time
3) Spark at the correct time and voltage

Take any one of them away and it doesn't run. I haven't turned blue in the face so I feel it is safe to assume that the air part isn't the problem. That leaves fuel and spark.
If you have a code reader that will also save data, chose a parameter such as the crank position sensor (cps) to measure and go for a drive.
If the reader has problems communicating with the pcm during the drive and doesn't lose power on the obd connector, that would give a clue to an issue with power to the pcm or the pcm ground.
If it has trouble capturing data for the cps, then might be a bad cps.

If you have a fuel pressure gauge, leave it connected but not where it will get damaged. Go for another test drive. When it dies the next time, check the fuel pressure. If it is 0 then there is an issue with the fuel system.

You have noted that your location is "US". That really doesn't help that much. The northern states salt roads in the winter which introduces a corrosion problem to the electric side of things. So, are you in a salt state?

 

[r0llinlacss]

Look at the problem logically.

In order to run the engine needs 3 things:
1) Air
2) Fuel in the correct amount and time
3) Spark at the correct time and voltage

Take any one of them away and it doesn't run. I haven't turned blue in the face so I feel it is safe to assume that the air part isn't the problem. That leaves fuel and spark.
If you have a code reader that will also save data, chose a parameter such as the crank position sensor (cps) to measure and go for a drive.
If the reader has problems communicating with the pcm during the drive and doesn't lose power on the obd connector, that would give a clue to an issue with power to the pcm or the pcm ground.
If it has trouble capturing data for the cps, then might be a bad cps.

If you have a fuel pressure gauge, leave it connected but not where it will get damaged. Go for another test drive. When it dies the next time, check the fuel pressure. If it is 0 then there is an issue with the fuel system.

You have noted that your location is "US". That really doesn't help that much. The northern states salt roads in the winter which introduces a corrosion problem to the electric side of things. So, are you in a salt state?

Yes, I'm in a salt state.

I checked fuel and it had tons of pressure.

I checked spark and it shocked me... so I assume it had spark.

Does the CPS control the injectors as well?

The code reader is a just a basic reader so I can't read any data.

And it was raining today... I've read alot about these windshields leaking on the GEM module, but would that kill the engine?? Maybe that would explain why it runs fine in a certain spot but won't drive??

EDIT: It doesn't lose power when it dies, just the engine dies, does that rule out the GEM module?

 

[r0llinlacss]

I just read that the CPS would cause a no-start condition if they go bad, but could it be intermittent? Or once they're done, they're done?

I forgot to list the parts replaced by the previous owner:

New vacuum lines (although I still found a leak and fixed one)
All new spark plugs
New EGR Valve
New fuel filter

I've replaced:
Two coils
Fuel pump


Also, it's hard to start and doesn't want to stay running when the engine is cold.

 

[stamp11127]

New thread started here:
http://www.expeditionforum.com/f42/some-issues-29399/

This thread is closed.