help with p1668
#1
08-20-2009, 10:31 AM
help with p1668
hey guys, I'm in need of you help if it all possible.My dad has a '99 2500 4x4 and one day he shut the truck off and it would not start after. we are getting fuel up to the fuel filter,so we checked to see if we are getting fuel past the injector pump.we are not 
. we checked to see if it was throwing a code,It's throwing a p1668.now everywhere i looked it says that it's a connection problem between the ecm and the idm(or fpcm,I don't remember which).some places say that you need to replace the injector pump to fix this and some places say you don't.They say to check all the connections on the module for the injector pump.ok, i looked at the injector pump and i can see the module connected to it.can you just replace that module?.If so where can you find one?.I've looked everywhere and noone really know what i'm talking about.If anyone can help me out with this i'd really appreciate it
.when it comes to diesel engines i'm kinda in the dark.
. we checked to see if it was throwing a code,It's throwing a p1668.now everywhere i looked it says that it's a connection problem between the ecm and the idm(or fpcm,I don't remember which).some places say that you need to replace the injector pump to fix this and some places say you don't.They say to check all the connections on the module for the injector pump.ok, i looked at the injector pump and i can see the module connected to it.can you just replace that module?.If so where can you find one?.I've looked everywhere and noone really know what i'm talking about.If anyone can help me out with this i'd really appreciate it.when it comes to diesel engines i'm kinda in the dark.
#2
08-21-2009, 02:07 AM
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It could be in the wiring. I would take the time to trace wires and make sure they are not cut. its possible that its just wiring that is a vp44 pump i would think and if those don't have power it don't work
I'll message you tomorrow I'm going to bed I have the diagrams and stuff ill look it up and message you only for cummins not the dodge end of it though wire that you will be checking is to injection pump to the ecm and you will unplug the both connectors on the computer ttyl
I'll message you tomorrow I'm going to bed I have the diagrams and stuff ill look it up and message you only for cummins not the dodge end of it though wire that you will be checking is to injection pump to the ecm and you will unplug the both connectors on the computer ttyl
#3
08-21-2009, 08:56 AM
#4
08-21-2009, 11:05 PM
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I would wait and see what the power supply to the vp44 pump is like their is a plug on that pump that if you just take the time and check the power to it.
But I looked around today and couldn't find my schematics for the 5.9 with a vp44. I probly loaned them to someone at the shop but i asked a few guys but said no My boss is back to work monday and he has them in his desk that is locked.
I will tell you that when you check the wiring on a Cummins. never use a testlight use a multimeter that is ECM safe or computer safe those are about $250 and up Their is cheaper ones but may not be computer safe and you will need a very expencive tool its called paperclips you can buy them anywere
DO NOT stick the probe in the hole use the paper clips to stick in the hole It may mess up the plug on the computer and cause it to not make a good contact when you plug everything back together.
Also careful when you unplug the computer try not to let the plug sag try to get it to pull straight out. the pins that is on the computer can break and you not notice then you have problems when done
can you PM me your email address I will Email you the pin locations and the wiring diagram AS soon as i can
Also this goes for everyone I have the Cummins wiring diagrams so if anyone wants to check wiring they can ask me I'll help anyway i can
Is their anything comming out of that vp44 anyfuel at all.
If their isn't any fuel comming out I would almost bet that its electical.
not the pump.
Once i was messing around and unplugged that pump and it won't start with out that plugged in. But I have a jumper box that i plug in with a switch to turn on the pump with out the computer. but its full throttle or idle full throttle is 2200 rpm on industrial engines that is what i work on.
I miss the old inline pumps and non computerized engines they are more reliable and easier to work. I have only been doing this for 13 years started while i was in highschool. but when i started they didnt even dream of having a computer running a diesel engine.
But I looked around today and couldn't find my schematics for the 5.9 with a vp44. I probly loaned them to someone at the shop but i asked a few guys but said no My boss is back to work monday and he has them in his desk that is locked.
I will tell you that when you check the wiring on a Cummins. never use a testlight use a multimeter that is ECM safe or computer safe those are about $250 and up Their is cheaper ones but may not be computer safe and you will need a very expencive tool its called paperclips you can buy them anywere
DO NOT stick the probe in the hole use the paper clips to stick in the hole It may mess up the plug on the computer and cause it to not make a good contact when you plug everything back together.
Also careful when you unplug the computer try not to let the plug sag try to get it to pull straight out. the pins that is on the computer can break and you not notice then you have problems when done
can you PM me your email address I will Email you the pin locations and the wiring diagram AS soon as i can
Also this goes for everyone I have the Cummins wiring diagrams so if anyone wants to check wiring they can ask me I'll help anyway i can
Is their anything comming out of that vp44 anyfuel at all.
If their isn't any fuel comming out I would almost bet that its electical.
not the pump.
Once i was messing around and unplugged that pump and it won't start with out that plugged in. But I have a jumper box that i plug in with a switch to turn on the pump with out the computer. but its full throttle or idle full throttle is 2200 rpm on industrial engines that is what i work on.
I miss the old inline pumps and non computerized engines they are more reliable and easier to work. I have only been doing this for 13 years started while i was in highschool. but when i started they didnt even dream of having a computer running a diesel engine.