Cummins Diesel Forum banner
Cancel

No LP prime but the truck runs like a top

608 Views 4 Replies 3 Participants Last post by  99coalroller24V, 
Answerwi
My truck stopped priming and/or bump start priming about a week ago. My fuel pressure is 15 psi at idle and 13 psi at WOT. My Raptor 150 LP is new and runs only once the truck is running. I've been through the LP harness and relay and all is good. I can bypass the relay and the pump runs fine. That said, I'm getting only 8.5 volts from the ECM with the key in the "ON" position. Once the truck is running I'm getting 12 volts from the ECM. Maybe a coincidence, but it just started getting cold (30 - 40 degrees) here in the last couple of weeks. I've been through similar threats that are resolved with a new ECM. They however, have other issues like wait to start light not working or not turning off, rough idle, codes, or no start. My grid heater is working fine, the wait to start light comes on as usual, no codes and the darn truck runs great. Any feedback as to what I'm missing here would be most appreciated.
Reply
Save
Like
1 - 5 of 5 Posts
Answerwi
Side note: I also need to crank up my posts to 50 so I can get back in to the classifieds and look for a new ECM...
Reply
Save
Like
Cumminspal
Maybe the grid heaters are pulling the batteries down too much? That wouldn't explain why the lp isn't running when you bump the starter though. Just a thought. If nothing else, you can reply and add to your post count.


Sent from AutoGuide.com Free App
Reply
Save
Like
  • Like
Reactions: 1
Answerwi
Good call on the grid heaters pulling down the voltage. That said, I installed two new batteries this week and also disconnected the grid heaters to see if they were the cause...no luck, still no prime. Thanks for another post.
Reply
Save
Like
99coalroller24V
fierjgwergewgweg edited
Reply
Save
Like
1 - 5 of 5 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Cummins Diesel Forum
A forum community dedicated to all things Cummins Diesel! Originally founded for owners and enthusiasts of Cummins powered Dodge pickups, the Cummins Forum has expanded to include ALL Cummins Engine applications! Come join the discussion about reviews, drivetrain swaps, turbos, modifications, classifieds, builds, troubleshooting, maintenance, and more!
Full Forum Listing
Explore Our Forums
03-07 Performance Parts Discussion 03-07 Powertrain 2013-2018 General Discussion 98.5-02 Powertrain 98.5-02 Performance Parts Discussion
Top