Smoking pmd

[MrMarty51]

Hey Guy`s Rob here in Australia , I mounted 2 x PMD`s one with a #6 resistor and one with a #9 I run the #9 but if im getting low on diesel and the next service centre is 1000Ks away swap it over to the one that drinks less ,,
Anyhow an update im in hospital NEW KNEE ,,, will be back on the ROAD BLOODY SOON ,,

Dang Man, praying for fast and full recovery. Get well quick and give us some more a them down under tours.

 

[WarWagon]

Hey Guy`s Rob here in Australia , I mounted 2 x PMD`s one with a #6 resistor and one with a #9 I run the #9 but if im getting low on diesel and the next service centre is 1000Ks away swap it over to the one that drinks less ,,
Anyhow an update im in hospital NEW KNEE ,,, will be back on the ROAD BLOODY SOON ,,

Not going to change the MPG as your foot controls the fuel burn rate. And it's such a small change anyway.

Do your PT with that new knee. Long term it will be worth it.

 

[Turbine Doc]

The misconception is with # X resistor you will get X-mm fuel increase or decrease in delivery...Yes and No...this is a calibration resistor wherein on a test stand when IP is built new or rebuilt the total volume of fuel delivered at fixed rpm = 80cc/3 at 3000 rpm (I think....I'll have to refer to the spec it has been a while), you then use value resistor to achieve/adjust to test spec delivery; on the test stand there is no acceleration schedule accounting for boost-coolant temp-airflow etc. the variables the PCM monitors while driving and adjusts fueling according to the variables.

Anyway in your truck the PCM controls the delivery to the fuel table in the program then monitors and regulates final fuel per load demand on engine, so basically when you demand fuel you could get a higher or lower fuel delivery at initial demand command modified by the resistor installed, but once demand is met the PCM then supplies/modifies fuel per tables in the program be it a stock-economy-mild-wild program tune, so with a say #9(4mm/3) you could get a crisper acceleration than you could from a 5(0mm/3) resistor; with (2)similarly matched IPs one IP a littler fresher than the other in terms of internal wear the net effect may not be the same.

I've run #5 , 7 & 9 honestly have not seen enough difference to brag about, one could go to #14 theoretically but I've been told that if going above a 9 your IP is in need of overhauled if healthy you will set a code that will limp the fuel rate of the IP...I don't know that for a fact # 9 is all I have ever ran myself.

Lastly I'll add if you do not do a TDC offset learn command the value stored in the PCM is the value you will be operating with regardless if you have a higher resistor or .....wait for it...no resistor installed....

I was on a mission once to prove "Steak Sauce vendor" wrong his change on the fly "variable fuel rate controller was crap; I ran without the resistor in mine for a year no issues or changes in fuel delivery until I commanded the TDC offset learn after that I got a no start, and also resistor reference missing error code in the PCM.

 

[WarWagon]

My 1995 burb project had sat for a year with a blown engine, no batteries, finally put an engine in it, ran 6 months and then finally popped a code for a missing resistor.

 

[Tinker]

Yep, I removed the other sensor plug to adjust ip timing and forgot to put it back.
Its idling fine now.
thanks

Howdy,
I'm a newbie to this site. I have a 1996 GMC Serria 6.5 with 177k miles. While driving along the truck ran away. I quickly turned the key it stopped. I managed to coast to a driveway. Had it towed back home. At home,I noticed when the key is turned on to wts smoke started comming out of where the pmd is(still on the side of the IP) and I could hear a sizzle as if something was burning. I unplugged the pmd connector turned key no smoke or sizzle. Ordered new pmd from ATRACYPART(not sure what manufacturer)plugged in, no smoke but engine will not start, not even trying too. Purged valve at the fuel filter good fuel there. Did the same with the t handle on the IP, seemed to have good fuel. Checked shut off solenoid looks good, I removed it and it's pulling in with key on. Loosened injector line no fuel dripping out when cranking. Removed 4 glow plugs driver side did the cranking sequence and no fuel. Could I have a air locked IP? Assuming the new pmd is good I plan on removing the 8 GPs and try to get fuel drip at the injector. Any advice would be great.
Thanks

Thanks for detailing this failure. I had these exact symptoms on a 94 Suburban. Nobody would believe my PMD was smoking. The truck sat for a while and I'm just now getting to it. Anyway, this thread will be really helpful in tracing my issues.

 

[Tinker]

I'm doing continuity tests from plug to harness. Checking each wire for opens or shorts and any fuses along the way.

I'm in the middle of a similar troubleshooting process. My next step is pulling off the intake manifold to go through the valley harness. Are there a lot of inline fuses/fuseable links to check?

 

[Husker6.5]

I'm in the middle of a similar troubleshooting process. My next step is pulling off the intake manifold to go through the valley harness. Are there a lot of inline fuses/fuseable links to check?

None that I know of, just a couple of connectors to check each side of and to definitely look for crunchy/broken/missing insulation inside the harnesses that is either shorting to another wire or to ground via the manifold/valley.

 

[MrMarty51]

Welcome to the forum Tinker.