• Welcome to The Truck Stop! We see you haven't REGISTERED yet.

    Your truck knowledge is missing!
    • Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
    • We have tons of knowledge here for your diesel truck!
    • Post your own topics and reply to existing threads to help others out!
    • NO ADS! The site is fully functional and ad free!
    CLICK HERE TO REGISTER!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

Are These Symptoms of a Bad PMD?

I don't have a truck to try it on anymore. It is brand new, so would expect it to be good.
 
I talked to the shop about 20 minutes ago. Their rebuild guy is sure it's that solenoid thing. However, they had no problems waiting until I brought in a PMD to try, either. Good advice, everyone - thank you.

Any thoughts on the pulse width thing?
 
JiFaire said:
I totally agree with Leo, Dennis ... if you need a new IP, chances are good you need a new PMD, also.

However, I'm still concerned about your fuel flow. Did you actually get fuel out of the line with the LP running? It's not uncommon for them to make lots of noise, and SOUND like they work, but be pumping nothing.

If your PMD was causing the stalling, the truck wouldn't have re-started itself when you let off the fuel unless you have a standard... but if you had 'bogging' (lack of fuel), the truck would appear to recover when you let off the pedal. Snotty sock can also cause those symptoms... and they would appear quite suddenly and get rapidly worse, if you got some bad fuel...

I would make sure I had full fuel flow making it to the IP with the key on, before I started changing either PMD or IP.

Then PMD (Like Leo said, everybody needs a spare), THEN (and only then) change the IP.

My thoughts, worth what you paid for them.
Click to expand...

Yes, fuel came out of the line with LP running.

The "stalling" while driving I had wasn't really stalling. If I let off the pedal quick enough, the engine would stay running (it never died and then re-started itself - you're right, that would only be with a manual). If I kept my foot on the pedal, then it would die completely. A couple times, I was able to shift into neutral (while still moving on the highway) and re-start successfully.
 
Could be a loose wire connection on the solenoid,i've seen a few of those
The solenoid them selves are pretty sturdy build.
I would tweak the pins on the PMD ever so slightly for a more positive contact.
 
Burning oil said:
Your order will go out today. Thank you.
Click to expand...

Yeah, you're not kidding "today"! Less than 4 hours after placing the order, I received an email saying "your order has been shipped"! Thanks!

I took everyone's advice and ordered a second PMD (grey box Stanadyne), as well. Also got the heat sink kit and Leroy is making me a short quick-connect cable to go back and forth between the FS driver and the Stanadyne driver. If the one that is currently on the pump is still good, well, then I guess I have 2 spares!
 
UPDATE UPDATE UPDATE

First and foremost - thank you all for the guidance!!!!:)

Now, what do you think of this?:???:

The results are back from the shop - I pick up the truck tomorrow. Turns out the culprit was the PMD. They hooked up one of the new ones I bought and it started right up. They took it for a drive and started blowing LP fuses. They replaced the LP saying it must have a short in it. So why would a bad PMD cause those funny Pulse Width readings? They didn't have an answer for it - said it was "really weird".
 
Shameless bump...:eek:

I'm primarily curious about the initial diagnosis where pulse width #'s where found to be stuck at either 279.38ms or 0.00ms - nothing in between. That's what lead the shop to think it was the solenoid on the back of the pump. They were stumped as to why a new FSD corrected the problem. Any thoughts about that?
 
IIRC the FSD controlls the solenoid.
F-Fuel
S-Solenoid
D-Driver


Or am I out in left field?????
 
Well, I wondered that, too. But, then I thought "why was the shop confused about it?"

And, why in the heck is the saying "left field"? I mean, don't you always put the kid who can't catch in right field? Boy, I remember one kid - Danny - I think we were about 13 or 14 at the time... his thing "to do" in the dugout was to put the catcher's cup over his face and run around pretending it was a "Jason" mask. Oh... he was not the catcher - and he played right field.
 
Last edited:
You must log in or register to reply here.
Back
Top