Another Stalling Saga..... :-(

[MR.E]

Well…my time of reading about others stalling issues are over. Spent most of the weekend chasing electronic phantoms.

My truck started the “fishbite” trick about 2 months ago and progressed to stalling. It was stalling infrequently (1-3 times a month) and would always restart while rolling from neutral…but it got more frequent.

Went through and cleaned all the grounds with no affect on stalling frequency.
Unplugged my remote PMD (Heath) and went back to stock but it has gone bad. Bummer since the pump/pmd was replaced 14k ago under warranty.

Replaced the optical sensor harness and the stalling is still there.

Here is the thing that is vexing me. During my grounding fun I noticed when I have the AM radio on, I hear “electronic engine noise”, some times called alternator whine. I suspected a bad ground feeding the dash (G202) but it is good and so is the connection at the radio.

Suspected the alternator at this point. I checked for AC but none is present. Just to be sure, I pulled the serpentine and re-started. It is still there.

So…what can produce a ground current or RF that is synchronous with motor RPM? Could the IP be the cause? I also hear a faint pop/scratch when the drivers door pin is operated.

Thoughts?

For the record:
Lift pump is good 7psi at idle ,3 at WOT
Fuel filter changed 4k ago
No codes
New motor 6k ago.

Help…starting to think Craigslist is the best fix….

[Robyn]

The IP is definately a possibility and certainly a possible source of electrical "Noise"

Now, does the stalling follow a particular amount of fuel in the tank??

So does it make any difference as to how much fuel is in the tank when you get the fish bite and the stalling.

My dually will do this if I let the tank get below 1/4 or so and work it hard.

The issue here is a safety valve in the pickup tube that is there to allow fuel to enter if the sock gets plugged. The valve can go bad and allow air to enter if the valve becomes uncovered (Low tank level)

With no codes present, I am suspect of air and or just bad luck with the electronics.

I went through all the tests on mine and replaced the PMD, the filter harness and proceeded to pull my hair out.

I was low on fuel and was heading home to do more diagnostics and stopped to fill the tank.
The issue vanished after the fillup.

I ran the fuel level down over the next week or so and the gremlin came back, refilled and the gremlin was gone.

Answer to issue found


Another thing to do is to install a clear piece of tubing on the return line from the IP and run it up arouind the wiper blades so you can observe the flow. If during a fishbite/stall you see air bubbles, Poof you have the reason and then its only a matter of finding the source of the air getting into the system.

Let us know

Robyn

[More Power]

Everyone with the electronic 6.5 should have a known-good FSD/PMD on hand as a spare and have a remote mount so it can be easily changed. Consider it as important as a spare tire.

I'm currently recommending the DTech (http://www.thedieselpageforums.com/adpeeps/adpeeps.php?bfunction=clickad&uid=100000&bzone=directlink&bsize=468x60&btype=3&campaignid=684129&adno=32&transferurl=http%3A%2F%2Fwww.dtechproducts.com%3Fl eadsource%3D4) aftermarket replacement.

Jim

[MR.E]

Sorry for the late posting. Career and MBA have kept me really busy but wanted to provide closure to this for future reference.

It turned out to be a bad PMD.

I installed the heath PMD but put the aluminum plate on the back of the skidplate vs front as designed by Heath and well....let's just say reading directions is a good thing.

New PMD and proper install of the heat sync got me up and running.

[Robyn]

Glad all is well.

As Jim Mentioned, having a spare is a good thing.

My first choice for a spare setup is getting a cooler that mounts to the top hat on the manifold.

Mount a good PMD with the proper resistor and have it and a proper wrench stuck in the ditty box. On a cold and dark night the little beast can be attached to the manifold in a couple minutes and the plugs swapped.

Given that the manifold is not the best place for the cooler to be, having the spare to go there is a great "get me home" thing and can be handled without having to crawl under the beast under nasty conditions.

I have an Old SOL D unit mounted in the Burb for just such occassions.

Takes only about a minute to jump out, toss open the hood, swap the plugs, slam the hood, fire up and drive off.

The down under mount is perfect for the long term but not too great when you have to access it in your good clothes under worst case conditions.


Have fun and be safe

Robyn