Lift pump delay
#11
#12
#13
its got to be a wiring problem. do you have a digital ohm meter?, if so, check the draw to the pump, you may have something limiting the signal, not sure what would do that but cant hurt to check
Course, you could solve this by hard wiring in the pump to the battery and using a toggle switch or just get you a FASS,Raptor or some other aftermarket lift pump
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or even hard wiring the power wire from the pump into a keyed 12v source, such as the red wire with a green stripe on the firewall above the engine. this would eliminate the toggle switch, either way, id still fuse it at the minimum
Course, you could solve this by hard wiring in the pump to the battery and using a toggle switch or just get you a FASS,Raptor or some other aftermarket lift pump
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or even hard wiring the power wire from the pump into a keyed 12v source, such as the red wire with a green stripe on the firewall above the engine. this would eliminate the toggle switch, either way, id still fuse it at the minimum
Last edited by dukeboy_318; 01-30-2011 at 11:03 PM. Reason: Automerged Doublepost
#14
If you "hard wire" the Lift Pump to the DC bus (somehow) - be sure to include a safety circuit that disables power to the lift pump so you don't have to do it manually.
A common design uses a Normally Open Pressure switch (closes at about 5 psig) that is screwed into an oil pressure port. When the engine is running (and therefore Lube Oil pressure is greater than 5 psi (it better be!!)) - the switch is closed and the LP can run. If the engine shuts down - the fuel pump looses power and stops pumping diesel fuel (an important feature in case of an accident!!)
A common design uses a Normally Open Pressure switch (closes at about 5 psig) that is screwed into an oil pressure port. When the engine is running (and therefore Lube Oil pressure is greater than 5 psi (it better be!!)) - the switch is closed and the LP can run. If the engine shuts down - the fuel pump looses power and stops pumping diesel fuel (an important feature in case of an accident!!)
#15
#16
Not running. I checked it with pressure gauge. It appears to be an electrical issue not getting voltage out of the ecm
#17
SAME ISSUE!!
(98.5 cummins) truck starting process - turn key to run position....(5 to 8 second delay)... WTS light appears/ AIRDOG lift pump pulsates simaltanuously, turn key to start position, truck starts. Truck will NOT start unless lift pump runs. have had trouble with low fuel press alarm alerting randomly. truck add ons include EDGE JUICE w/ ATTITUDE, Air Dog Lift Pump, recent VP44 install (within 5 years) chip, and lift pump install done by previous owner, known personally(dumbshit)
#18
RRCustom,you are not alone! I've been trying to work though the exact same issue as you for the past year or so..
Just to be clear, When I turn on the key the wait to start light does not come on and the lift pump does not run. The engine will not start until the wait to start light come on.
So sometime near the end of 2009 early 2010 I took my truck to the local Cummins shop to see if they could figure it out. I had given up on finding a soloution online and really just wanted the damn thing fixed. After having the truck for a few days they decided to reflash the ECM. According to Cummins the truck was fixed. Nope, two days after I picked up the truck it did the same damn thing.
OK so spring rolls around and BAM! the truck begins to start normally 100% of the time. All summer long EVERYTIME I turn the key she fires right up. Near the end of fall/ begining of winter, the same old problem popped back up.
I'm wondering if there isn't some sort of issue with an outside temp sensor but I'm not sure how they would effect the WTS light or the VP44 sending fuel...
I should add that I purchased this truck new in 99 and other than a few vp44 pumps and several lift pumps, she's running stong a alomst 400K miles on the clock
If anyone has any bright ideas about this I'd love to talk on phone. Perhaps with a real time conversation we can figure something out..
Mike
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On a side note:
Yesterday morning the heater grids decided to stop working and the WTS light NEVER came on (it was 28deg F.outside) The truck started but boy was she rough. Through out the rest of the day the truck started right up but the wait to start light would NEVER come on. I plugged the truck in last night so this morning she fired right up. A couple of hours ago I decied to swap out the diesel/fuel heater realy with the one labled "trailer" in the fues block under the hood. The wait to start light still does not come on but the heater grid DOES come on after the engine starts. (I can watch the volt meter fall and rise as it cycles on and off. Now the engine was already hot so maybe the wait to start light and the heater grid may not come on anyway.. ALSO, the I still don't hear the lift pump run at all with key on as it should.
So far today I've started the truck at least 14 time and every time she started right up. Wowever not once did the WTS light come on and not once did I hear the lift pump run with key on.
leaving me saying WTF is up withthe WTS.. :-)
Thanks
Mike
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OK I can also confirm that there isn't any voltage going to the life pump at key on or with the engine running. I disconnected the lift pump and hooked up a volt meter to the supply side of the connection. I'm not seeing any voltage at all with the key in the run position even if I bump the starter. The truck starts up and runs fine with out the lift pump so I can assume that I don't have any air leaks in the fuel system.
So here the update list:
at no time does the wait to start light come on (new this week)
At no time is the lift pump seeing voltage
the intake heater grid does not light up when you turn on the key but it fuctions as it should when you start the truck. Meaning that when you start the truck warm, not cold the grid will cycle on and off at idle.
I have direct wired the lift pump with a toggle switch for the time being.
BTW I have also looked at the ECU connector and can't find any loose conections on any of the pins. So if the lift pump is powered directly from the ecm, has my ecm failed?
cheers
Mike
Just to be clear, When I turn on the key the wait to start light does not come on and the lift pump does not run. The engine will not start until the wait to start light come on.
So sometime near the end of 2009 early 2010 I took my truck to the local Cummins shop to see if they could figure it out. I had given up on finding a soloution online and really just wanted the damn thing fixed. After having the truck for a few days they decided to reflash the ECM. According to Cummins the truck was fixed. Nope, two days after I picked up the truck it did the same damn thing.
OK so spring rolls around and BAM! the truck begins to start normally 100% of the time. All summer long EVERYTIME I turn the key she fires right up. Near the end of fall/ begining of winter, the same old problem popped back up.
I'm wondering if there isn't some sort of issue with an outside temp sensor but I'm not sure how they would effect the WTS light or the VP44 sending fuel...
I should add that I purchased this truck new in 99 and other than a few vp44 pumps and several lift pumps, she's running stong a alomst 400K miles on the clock
If anyone has any bright ideas about this I'd love to talk on phone. Perhaps with a real time conversation we can figure something out..
Mike
---AutoMerged DoublePost---
On a side note:
Yesterday morning the heater grids decided to stop working and the WTS light NEVER came on (it was 28deg F.outside) The truck started but boy was she rough. Through out the rest of the day the truck started right up but the wait to start light would NEVER come on. I plugged the truck in last night so this morning she fired right up. A couple of hours ago I decied to swap out the diesel/fuel heater realy with the one labled "trailer" in the fues block under the hood. The wait to start light still does not come on but the heater grid DOES come on after the engine starts. (I can watch the volt meter fall and rise as it cycles on and off. Now the engine was already hot so maybe the wait to start light and the heater grid may not come on anyway.. ALSO, the I still don't hear the lift pump run at all with key on as it should.
So far today I've started the truck at least 14 time and every time she started right up. Wowever not once did the WTS light come on and not once did I hear the lift pump run with key on.
leaving me saying WTF is up withthe WTS.. :-)
Thanks
Mike
---AutoMerged DoublePost---
OK I can also confirm that there isn't any voltage going to the life pump at key on or with the engine running. I disconnected the lift pump and hooked up a volt meter to the supply side of the connection. I'm not seeing any voltage at all with the key in the run position even if I bump the starter. The truck starts up and runs fine with out the lift pump so I can assume that I don't have any air leaks in the fuel system.
So here the update list:
at no time does the wait to start light come on (new this week)
At no time is the lift pump seeing voltage
the intake heater grid does not light up when you turn on the key but it fuctions as it should when you start the truck. Meaning that when you start the truck warm, not cold the grid will cycle on and off at idle.
I have direct wired the lift pump with a toggle switch for the time being.
BTW I have also looked at the ECU connector and can't find any loose conections on any of the pins. So if the lift pump is powered directly from the ecm, has my ecm failed?
cheers
Mike
Last edited by extra330; 02-03-2011 at 07:10 PM. Reason: Automerged Doublepost
#19