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Discussion Starter #1
So, as the title states, I installed the FASS 150 on my 2003 about 4 months ago and since the install the truck has had an extended crank before it will start. Before I installed the FASS the truck would do what I will call "2 cranks" before it would fire, now it takes "4-5 cranks" before it will start. I have been just living with it the way it is but I am over it and want to figure out what the issue is. If the truck sits for any period of time the starting issue is worse. For example, I let the truck sit for a week and went to start it two days ago. In order to get the truck to start I had to go through "3 cycles" of "4-5 cranks" resetting the key each time before the truck would start.
So, it seems at first like the system is losing prime while it sits. I have looked all over the FASS system at any and every spot where there could be a fuel leak and have found no fuel residue anywhere. I have double checked all the fittings with a wrench and nothing is or was lose. When I installed the system, I bypassed the factory filter and lift pump on the block and went straight to the CP3. The truck did not have the "dealer installed in tank pump conversion."
When the truck is running it runs fine without issue and my fuel pressure gauge reads 15-16 psi. I have read that 18 psi is more normal so I don't know if mine is too low or not. The Fuel Rail Pressure is reading 5,000-6,000 psi at idle. From what I have read, these are normal readings. The truck is mostly stock, it has the stock CP3, the stock injectors, and a Bully Dog Power Pup, which seems to do absolutely nothing for performance from what I can tell. The truck is an S.O. motor with a 5 speed and 90,000 miles.
When I turn the key to the run position I can hear the lift pump running, but it doesn't seem to run every time I turn the key to the run position. I thought that maybe the pump housing had an internal switch and if the system pressure was up then the pump wouldn't run if it didn't need to, but maybe that is not the case. If I turn the key to the run position I can let the pump run until it shuts itself off and it has no change on whether the truck starts any faster. I have tried completely unhooking the lift pump and starting the truck without any lift pump at all and it doesn't make the truck start any faster or slower. When I do turn the key to the run position and let the pump run the fuel pressure gauge doesn't come up, it stays between 0-2 psi the whole time. If I bump the starter for a crank or two and then turn the key to the run position, then the fuel pressure gauge will come up to 15 psi while the pump is running.
When I installed the system, I did install the return line into the Fuel filler neck which I have read from some guys that this can be an issue when you get low on fuel, but this is happening with a full tank so I don't believe that is the issue. I have not tried the bucket test yet to try and eliminate if I am having a problem within the tank itself or not.
Also, sometimes it seems that the truck won't start until I release the key, so, if I am cranking the truck over and it's not starting, I give up and say ok it's not going to start this time, when I let of the key, the trucks fires right up. This to me seems like it would be a different issue altogether, like a power draw issue while starting.
I am unsure of what else to look for, I know that I could be having an issue with my injectors or fuel rail, but it seems to coincidental that this all started when I put the FASS on the truck, maybe something else happened to go bad at the same time, but because it all started right after the FASS install, that is why I have been focused on that as the culprit. Anyone have any input for me? It would be appreciated.
 

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When I do turn the key to the run position and let the pump run the fuel pressure gauge doesn't come up, it stays between 0-2 psi the whole time. If I bump the starter for a crank or two and then turn the key to the run position, then the fuel pressure gauge will come up to 15 psi while the pump is running.
When I turn the key on and the pump runs I have pressure to 16 psi almost instantly. I did keep the OE filter. It would seem that you have a leak that is going back to the tank. Try bumping the starter and let the pump run for about 15 to 20 seconds and then hit the starter. If it starts quickly then there is a leak somewhere.
 

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Discussion Starter #3
If I have an airleak then I can not find it to save my life. Everything is tight and I am afraid to tighten any fittings any more than they already are.. Not sure what else there could be..

So as a small test I drove the truck home from work, shut it off, sat in it in the driveway for about 5 minutes, I turned the key to the run position and the fuel pressure gauge read 14 psi...... I tried starting the truck and it "seemed to be an acceptable" crank time. It has been like this so long that I can't hardly remember how fast it used to start.. Then I let it sit in the driveway for about 2 hours, ate dinner, went back out to start the truck again. Turned they key to the on position and the gauge read 5 psi and the pump was running but the gauge never came off 5 psi the whole time until the pump stopped....

I am confused and I am thinking that I don't fully understand something about the system in general......
 

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It sounds like you are not getting 12 volts to the pump all the time. You might try replacing the relay.
 
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