fishbiting with new pmd? wiring?

[qak]

Ok i bought this truck and it had running issues. New pick up and lift pump later and it runs great. However lately it died on me once, just like i pulled a coil wire on a gas motor. Also every once in a while
itll fishbite. Well this morning i was warming her up and decided to open the hood and look at stuff. I decided to move the wiring around and see if i had a bad connection. The wiring and the pmd look new. po said it was new and replaced because they thought that was the problem.

The issue is when i moved the wiring at the pmd connector (its on the side of the intake with a large heat sink) it skipped and i did it again and it died. Started right up again, so i tried to move the other side of the wiring where it goes from the new (supposed) pmd to the factory wiring and it skipped again. Should i replace this wiring or maybe use some dielectric grease for the connectors? thanks for your help

 

[JMJNet]

Does it have some sort of extension? If yes, may want to eliminate that extension.

If not, you may want to take it out and see if all the pins and cables are good.

Is there any code? what is the model year?

 

[qak]

No codes. 1995

 

[BigArt]

Have you seen this? It cured the fishbiting for me...

http://www.thetruckstop.us/forum/showthread.php?13188-Intermittent-“FISHBITE”-type-misfire-or-chuggle-in-the-1994-1995-GM-6.5&highlight=Intermittent+%93FISHBITE%94#top


But you should get the PMD/FSD out of the engine compartment ASAP.

Art

 

[qak]

so after reading the other thread i should clean up the connectors really good and put on some dielectric grease? should i also take out the rf harness and just plug in the remote pmd that i have and see if that takes care of it. It has only done it a small number of times but i dont like it at all. If i take out the rf harness then my pmd harness will just plug into the factory harness? do i need to take off the top part of the intake to get to that? thanks for your help

 

[WarWagon]

You did a good job with the "wiggle test". You found a bad wire or connector. I would replace the PMD extension just to be sure. Look at the PMD and make sure the connectors are clean and wiggle the pins in case one cracked the solder and came loose. The wiggling wire and engine skip is a sure sign you are wiggling a problem connection.

 

[qak]

Thanks ill take it off later and check connections. Maybe that's why my cruise doesn't work

 

[racer55]

If the IP ground wire is mounted to the heatsink,cut and extend(solder,heatshrink) it so that it can be returned to the factory location on the IP.

http://www.mamut.net/royh/newsdet9.htm

The second picture down shows its proper location.

If the harness was replaced at the rear of the IP on the fuel solenoid it could also have a connection problem there.

 

[qak]

Ground wire is in stock location. Should I remove the resister jumper harness?

 

[racer55]

If you are asking about the Optical Sensor filter harness then I would go a head and remove it to eliminate it as a cause.
Some trucks however require it to run so it is a test.

Something called ferrite core can be used around each OS leads to mimic the resistor harness.

 

[qak]

Ok weird. Thanks racer. So will I need to take off the top of the intake to remove the harness?

 

[racer55]

I didn't have to remove any part of the intake to get rid of the filter harness,it was an easy reach where it was.