[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

 

[cummins crazy]

Check for leaks in the supply line for the FASS. You could have a loose connection and lose the prime.

 

[cummins crazy]

What code is it?

 

[Cummins0512]

Checked for leaks and nothing. As for connections they're being run tomorrow but they did double check and everything was tight as can be so ya

 

[Cummins0512]

The code I forget but something about interruption in the download process if I recall

 

[cummins crazy]

Any codes when the truck died? Fuel delivery error? Is the FASS running?

 

[Cummins0512]

The cel came on but smarty couldn't read it. Pretty sure it's fuel delivery error thoigh

 

[cummins crazy]

Make sure you're getting fuel to the CP3. Then start chasing high pressure connections.

 

[Cummins0512]

The high pressure is all working it's been checked and double checked. Fca was replaced. Injectors are flowing close to perfect. Relief valve is fine. Tubes are torqued and good. The fass will fill a 5 gallon pale pretty quick when it's off cp3 but that's at bump start. Hard to tell. It's under load when I lose everything. Should have added that at the beginning I guess. It builds proper boost and all that so ya. Could it be electrical or he fact that when he fass was connected it wouldn't tune and then couldn't set it back to stock until I unhooked the fass?

 

[cummins crazy]

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.

 

[Cummins0512]

Ok well the fass is hooked up direct to the driver side battery. Would that be too much for it?

 

[cummins crazy]

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.

 

[Cummins0512]

Ok could it be the connection to the factory wiring harness possibly?

 

[cummins crazy]

It's worth a check. There’s really not much to the hookup / install of these pumps.

 

[Cummins0512]

That's true. It's just a mystery and is really starting to piss me off.

 

[cummins crazy]

Find out the CEL and that'll help narrow things down. There’s also smarter guys on here than me about this stuff.

 

[Cummins0512]

I wish they would chime in and lay some insight haha

 

[cummins crazy]

Ya I know. Diagnosing over the net is hard without certain details.

 

[Cummins0512]

Ya it's weird but still I don't know. I'm leaning towards electrical. But could it possibly be the fass itself?

 

[cummins crazy]

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?