Hard start FASS related?

[ASTAR]

Ok, so I got the good ol' 0216 code a while back but nothing had changed on my truck as far as any problems noticed. A week later, the check engine light went off, a few weeks later, the light came on again and I had a dead spot in the throttle. Under acelleration. I know this is all standard vp44 death stuff but here's my question.

I had a FASS put in (to protect the soon to be replaced vp44) and now the thing has no dead spot in the throttle but it is hard starting when it is warm.

I assume it is all due to the doomed vp44 but is there anything else that would be a culprit here? I'd hate to replace my vp44 and still have a hard start issue.

Could it be the pressure of the FASS making it not want to start or the new fuel line injesting some air somewhere?

 

[cumminspwr01]

From what I've learned usually when the truck is hard to start when warm it means you are real close to swapping out the VP. Do you know what kind of pressure you are getting from the fass. Usually if the VP sees more than 20psi at or before start up it would be hard to start. The fass shuld be pre-set to between 13-17lbs. It could be your problem if the pressure is too high but it could also be a problem with the starter too. Ubfortunately it really sounds like the VP. IMHO

 

[keimmmo]

When I relocated my lift pump back to the tank, I fed power to it from a relay. When I turned on the switch, I hit about 12-13 psi. I eventurally developed a hard to start hot problem. I bought a pigtail from Cummins and made an "extension cord" to hook the pump to the original wiring harness.



Now, when I turn on the switch, the pump runs for just a moment and the pressure goes up to about 12-13 psi and drops back to zero. The truck starts fine and the pressure goes up to 12-13 psi as soon as I release the switch.



It fixed the hard start hot problem! I have run it that way for about 3 months now and it hasn't missed a beat!



It is my understanding that hard start problems are common if there is over about 7 psi on the pump when you try to start. (Information from Schieds in Effingham. ) I don't know how your FASS is hooked up, but if you have too much pressure on startup, it could be the problem.



Steve

 

[Wiredawg]

ASTAR:



Go to a Cummins shop and have them check your VP-44 out. About $75. Truck shouldn't be hard starting due to FASS, I see about 5 to 7 PSI at startup w/ my FASS.



I had my VP-44 replaced before installing my FASS. It set codes but didn't light the check engine light. It was hard starting and right at the end started smoking white smoke w/ low power,



Good luck, Wiredawg

 

[ASTAR]

Ok, so yesterday I tried waiting about 20 seconds to crank and it seemed like it started right up when i did that. I say "seemed" cause there were a few times I just jumped in, went to crank and it wouldn't want to start and I forgot to wait but it seems to me that when I would wait, it would start.

Now what?

If it is too much pressure from the FASS, what can I do to remedy it and why isn't everyone having that problem?

 

[Wiredawg]

Astar:



Do you have a fuel pressure gauge connected? If you installed the FASS according to installation instructions, the ECM controls the relay to the FASS and it will only operate about 1. 5 to 2 seconds and spin up 5 to 7 PSI.



Other than that, I still think going to a Cummins shop and having them diagnose the engine is the most sure, unless you have a good 5-Star you trust.



Wiredawg

 

[ASTAR]

Originally posted by Wiredawg

Astar:



Do you have a fuel pressure gauge connected? If you installed the FASS according to installation instructions, the ECM controls the relay to the FASS and it will only operate about 1. 5 to 2 seconds and spin up 5 to 7 PSI.



Other than that, I still think going to a Cummins shop and having them diagnose the engine is the most sure, unless you have a good 5-Star you trust.



Wiredawg

Actually, I haven't had time to wire in my gauge yet so I'm not sure what pressure I'm getting. The only reason I hesitate to take it to a Cummins shop (besides not knowing where one is) is that I already know that the vp44 is on it's way cause of the code and check engine light. I bought a new pump but I just don't want to be dealing with this issue after the new pump is installed ya know?

 

[LowFly]

Hello,



For your hard start issue give this a shot:



When you know that you are going to have a hard start before you do anything pull the fuse in the wire harness going to the relay. (It is about 3" inches away from the FASS pump) Before starting your engine with the fuse remove be ready to shut the engine off immediately when it starts, allow the engine to run without fuel pressure can damage your injection pump. Now start the engine once started shut it off!!! I'll bet you that it started immediately with the fuse removed. If it started immediately you know have choices. You could put an on/off switch on the FASS System, get a lower psi spring or get the VP44 fixed. From what I understand the VP44 has a valve that opens to allow fuel into a chamber to allow it to start. As the miles ad up on the VP44 this valve begins to weaken and may remain closed with pressure.



Brad