new FASS but possible failure ..fuel psi reads 0
#1
new FASS but possible failure ..fuel psi reads 0
Just installed a FASS 150 Titanium and Edge CTS. All seemed to be fine. After priming the new pump, filters, and line, the truck started fine. 14 -17 psi at the VP44. Truck was running like a champ, drove it for about 15 miles or so around the house, monitoring fuel pressure, checking for leaks. All appeared great. Still reading 14 – 17 psi at the pump via the edge's digital gauge. Kinda wish I had another type of gauge, analog or a light, etc because then all of the sudden, luckily about ½ mile from the house, I glance at the fuel pressure – it reads 0. Horrified of vp44 failure, I pull it into the garage. Truck seemed to be running fine and not starving for fuel (but of course I took it real easy for that last ½ mile). I suppose it could be a defective fuel pressure senor, but I don’t think so. Before this happened, if I remember correctly, when the truck was off and I bumped the starter, and did not start it, I used to hear the FASS pump run for a bit. Now – nothing from the pump, but I hear a click from the front of the engine compartment. Could this be a bad FASS relay? If so, where do you get a replacement one …is it FASS specific? I was unsure how to jump the relay, as I think that would prove it. I checked the fuse to it, it is fine. Any ideas? Thanks!
#3
#4
Thanks all. I did a lot of looking around. Sure enough I did find a loose connection from the juice to the JAB connection. I suppose that could attribute to a 0 fuel pressure reading or the CTS just flaking out as the next day I noticed it wouldn't even connect to the juice and I got the “failed to connect” error. I fixed that, my bad there. I also read about possible FASSs locking up due to air or debris. Don’t know if this is true or not but I figured why not re-prime it, get any air out of the system. Since I’m new to the Edge/ CTS and this FASS 150 titanium – I’m curious about one thing: When you bump the starter, should the pump ALWAYS turn on and run for 25 seconds or so? Because it was doing that intermittently before and when it didn't run there was definitely power to it for about 25 secs. I verified that with a test light. I thought that could be an problem.
Or am I mistaken and could this be normal… could it possibly shut itself off in a second or two if there is plenty of pressure in the line? If so, I might be ok. I know one thing, now I’m worried so before I start the truck, I've been making sure the gauges are up and I monitor fuel pressure, then bump the starter, and verify pump comes on and pressure is up. Since I fixed the bad juice / JAB connection and re-primed the FASS, I haven’t had any issues (yet)..but it’ only been a day. When I get in to start it, pressure is low (1), I bump the starter, the pump runs, pressure comes right up (15 or so). I’ll check it out tonight too. I got the relay schematic – THANKS.
Or am I mistaken and could this be normal… could it possibly shut itself off in a second or two if there is plenty of pressure in the line? If so, I might be ok. I know one thing, now I’m worried so before I start the truck, I've been making sure the gauges are up and I monitor fuel pressure, then bump the starter, and verify pump comes on and pressure is up. Since I fixed the bad juice / JAB connection and re-primed the FASS, I haven’t had any issues (yet)..but it’ only been a day. When I get in to start it, pressure is low (1), I bump the starter, the pump runs, pressure comes right up (15 or so). I’ll check it out tonight too. I got the relay schematic – THANKS.
#5
You want low pressure at start up. Too much pressure to ip when trying to start can make it harder to start just make sure pressure is up after it starts. I'm not familiar with fass so not sure if that is normal or not. I would say its not normal but give fass a call or shoot em an email. The ecm controls when the pump comes on. Should be 2-3 seconds when the key is turned on and 25 when its bumped.
#6
#7
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