FASS/VP44 Install, won't start
 

Hi guys, I'm new to the forum, I have read it a lot and you are all very helpful, thanks a lot. Yesterday I installed a vp44 and went with a FASS system to keep the vp alive for longer. I couldn't get the motor to start after. I cracked the injector lines and put compressed air in the fuel tank and it finally turned over and started. Once it started, I noticed the check engine light was on.
Once I knew the truck ran with the new VP and FASS, I installed an Edge Juice. I got all the cables hooked in, I didn't do the trans temp sensor, and couldn't figure out the boost elbow, so I left those wires aside. Once I got it fully installed, I primed the system and made sure there is fuel getting to the injectors, but the truck won't start. I was getting codes 0122, 0230 and 0237 after the edge install (yesterday). Today I tried to start it again, no luck. It didn't throw any codes but after I cranked the motor, the odometer would flash BUS or BU5 and then go back to the regular odometer reading. Any idea what the problem could be?

Usually when it flashed BUS or w/e it actually is it indicates an ECM problem. Because I know when you delete the programming in the ECM the odometer reads NO BUS. So I'm guessing computer issue anybody wanna back me up on that?

I would have it looked at but to flash the ECM will cost big bucks.

try disconnecting the batteries to reset computer, before hooking batteries up check fuses and your wiring for the fass pump.
Question... did you disconnect the batteries before you started your fass install?
one more thing before disconnecting batteries you should return programming to stock...remove the edge programming
codes:
0122 = throttle position sensor/switch A circuit low input
0230 = fuel pump primary circuit malfunction
0237 = turbocharger boost sensor A circuit low

Thanks for the help guys, I got it sorted out. I had to completely uninstall the edge chip, disconnecting all wires. I got it to start w/out the chip, then reinstalled it. The issue must have been one of the connections, which I thought I had double-checked. I must have missed one (it was late!).

I am now noticing much better throttle response with the FASS even with the chip on the stock level.

One quick question though: when I accelerate off the line my fuel pressure sometimes drops to 1-3psi (thats not even on WOT). Under normal conditions I get 16psi under idle and 12-13 under WOT. Any ideas why this might be happening? It isn't happening every time I accelerate from a stop, but enough that it is has me worried (the new vp44/fass install was expensive!)

Thanks again for the help on this, I appreciate it.

Did you get the FASS 150?

No I ended up going with the FASS 95. Do you think the 150 would have been more benefitial?

I have an air dog 150, pulls 17-18 lbs at idle and running down the highway 65-70 drops back and forth between 15-18. Have never been able to pull it below 12 lbs with horse trailer and four horses no matter the grade.

You could try adjusting the return pressure spring, or try streching the spring out some. It may take some trial and error. Streching it might hold back enough fuel to increase pressure to the injection pump.

It may be your gauge. Try another on if you can. I have the FASS 150 and it stays at 17 psi no matter if I am pulling my fifth wheel, cruising town or hot rodding it. I do have the auto meter full electric sweep fuel pressure gauge. I love it. Even with the smarty set at level 6 I don't get any fluctuations. Hope this helps.

Have you ever had a lift pump replaced before?

Was the old one in the tank?

Perhaps you're trying to pull fuel through your old lift pump?

If not, did you replace all of the lines?

What kind of fuel pressure gauge are you useing, mechanical or electrical?