my 98 cummins quit me we just got through putting new front brakes on my truck and washed off under the hood and i drove it to my friends house about10miles and i parked it for about 3hours well i went out and started it up and drove it about a block and it died with the check engine light on it started back up and died instantly it did this about 3 times and then it wouldn't start so we got the four wheeler and pulled it back home and i turned the key forward about 5 times to run the lift pump and it fired up spit and sputtered and then ran perfectly i held it a about 1200rpm for about ten minutes without a problem i havent touched it since but the check engine light is still on any opinions on what it could be it has 88000 and it had a new lift pump and a vp44 put on it at about 63000 miles the tank is about 3/4full idk much about these electronic motors so any help is apprecitated

 

Get a code reader and see what she tells you. Sounds like a LP and IP issue.

 

alright i got the codes
p1689 no communication between ecm and inj pump
p1698 no transmission bus messages
p1693 mil fault in companion modual
so i plugged the test tool into the pump and it said if the truck didnt start the inj pump is bad but i plugged it in and the truck started so im assuming the ecm is bad? all the connection seem good and tight i just dont want to buy a 600 dollar ecm and that not fix it

 

Could very well be a bad ecm. Easy way to check is find an ecm and switch them out.

What fp are you seeing out of the lp?

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I'd bet vp is going. ecm's very rarely fail in these trucks and in the cases I've seen where they are fried they throw tons of random codes. 1689 tells you the electronics on the pump are cooked.

 

could it go out after only 20000 miles and looked at the ecm and it said remanufactured of 2006 but idk i really dont want to spend 2000 on a new pump how can i test to make sure so i dont go spending money on useless parts i cant afford taking to a shop im more of a do it myself kinda guy and idk on fuel pressure my truck is bone stock with no gauges

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and also my dad has a 2002 dodge cummins 3500 with the six speed could i use his ecm i dont want to mess it up because of the differences in the trucks but he is about the only one i can think of

 

No, you can't use his ecm. Trust me, friend, you're lookin at a bad vp. What "test tool" did you plug into the pump? Not sure I understand what you were talking about there.

 

my friend works at a truck shop and had this tool you unplug your plug in on the back of the inj pump and plug this tool in then it has a pos cable and a neg cable and you hook those to your battery basically it acts as your ecm i think but it has a hi/low idle button and a shut off button the instructions said to start the truck up if it starts and you push the hi low idle buttons and the truck hits high idle and low idle then you push the shut off button and your motor dies then then the inj pump is fine and that you should check ecm and or connections ill try to find some more info on it i just cant see why the last inj pump only lasted 19,000 miles with the updated lift pump

 

I had the same problem with mine ,died on the road but would'nt start.I know a guy with the diagnostic tool you're talkin about the only problem was he had to go do a job away from where we live.I troubleshot the pump with help from blue chips website and just ordered a vp pump and just waiting to get it and put it on.

 

On your way to getting a VP pump and wouldn't be a bad idea to get a VP-LP combo...!