mainer

Searched and couldnt find anything similar. Trying to fix a friends truck.

02 HO with FASS

Truck starts fine in the morning. When he goes from his house to his office, about 5 miles down the road, he will shut it off at the office then come back out to start it (short time), his lift pump will primp up, but his fuel pressure gauge wont move, he will start the truck, it will run for a couple of seconds then die. Then he will have to crank the truck for a little bit then it will fire, then his fuel pressure will slowly come up to 15psi.

I checked the voltage tonight on it and when he turns the key to the on position, when the pump only primes, he has 6-8 volts, then if he bumps the starter, the pump will show 12volts. (as it should do according to Mass diesel).

Now the odd part, It did it early this spring, when it was colder out, it ran fine all summer long, but now that its getting colder out again its doing it again.

any help much appreciated.

artswavn

Check to see the battery connections are clean and tight. On cold starts the heater grids are on and voltage goes WAY DOWN (plug a voltmeter onto the cigarette lighter or onto either battery).

If I were a lift pump and was only getting a measly few volts on cold mornings and then someone was cranking the starter I would go on strike!

Try starting out your day with a cold cup of coffee...

mainer

thats the thing it starts perfectly fine first thing in the morning after sitting all night. its after you drive it then let it sit for 30 mins it does this unusal start.

JoeCanuck

Is the pump getting power from the stock location or relayed from the battery?

mainer

power from stock location

JoeCanuck

My Raptor came with a wiring harness with all the plugs to get power from the battery using the stock plug as a trigger.

I believe the Fass pumps use significantly more power than the stock carters and might run more reliably getting power from the battery. It should cure your low voltage issue.

mainer

from what i've been told, the voltage is correct. the 6-8 before bumping then 12 after is what its supposed to be i guess.

JoeCanuck

I am a coward...I tend to run ever accessory off of a relay. I like to keep as much of the load off of the electronics as possible. It also makes for a more consistent supply.

dspencer

This may sound wrong but here is what happened to me. My starter started dragging a little. Almost not enough to notice. I started having the problem with starting whenever it was 1) hot outside or 2)after the engine warmed up. It seemed to take at least 30 seconds for the engine to fire.
On cool mornings it started right up usually.

I put the truck, while hot, on an incline. I could start the truck just fine by using the clutch. Even while hot.

I replaced my starter and just like that my truck has started properly ever since. Like it had never had a problem. Good thing too because I was thinking I was going to have to replace the IP. There were no codes.

fireram

Check the cables to the starter, mine was doing this last year, when I peeled back some of the wire wrap around the conection to the starter, most of the cable was coroded off. The truck seemed to be turning over quick, but just wouldnt catch on the first try....