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Losing fuel and rail pressure. Help!!!!

1483 Views 23 Replies 3 Participants Last post by  Cummins0512
K so about 3 weeks ago I installed a fass 150 with sump on my 05 cummins. I also did injector nozzles which are now 90hp. When I got it going it ran fine at first then half way to town it just dropped fuel and rail pressure and died. Then it would start back up and run for about a half a kilometer and die again. Keeps doin this. Double checked everything and everything is torqued properly and seems too be working. Now when I got it all finished I used my smarty jr to tune the truck and half way through the download it threw a code. So I unhooked the fass because that seemed to be the problem and it fully downloaded. I should also say I tuned it before my first test run. Any way that could b causing the problem? I set it back to stock and is at a buddies shop right now and they are stumped. Please I really need to get this truck back up and running before winter because I need it for towing. Thanks. Also did factory fuel filter delete
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Check for leaks in the supply line for the FASS. You could have a loose connection and lose the prime.
What code is it?
Any codes when the truck died? Fuel delivery error? Is the FASS running?
Make sure you're getting fuel to the CP3. Then start chasing high pressure connections.
Could the FASS be drawing a higher current somehow? Grounding out? If there's a draw on the ECM then the smarty will sense that and throw an error. So ya. It’s sounding like electrical now.
Shouldn’t be. That’s how mine is hooked. It'll help to find out what code for sure is being thrown. Make sure no wiring is pinched.
It's worth a check. There’s really not much to the hookup / install of these pumps.
Find out the CEL and that'll help narrow things down. There’s also smarter guys on here than me about this stuff.
Ya I know. Diagnosing over the net is hard without certain details.
Not sure how if it’s filling a bucket like you said. If you hear it, see it pumping fuel, and get fuel to the high pressure side, it sounds like the pump itself is good. So you say the Smarty won't download with the FASS hooked up?
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