hard cold start
#1
hard cold start
Gentlemen, I have a 2008 Ranger with a 3.0 V6 - 88k miles. It is hard to start only after sitting overnight. Fuel pressure at the schraeder valve is 62 psi at idle and 67 psi above 1200 rpm. Pressure drops off slowly until 0 psi overnight. Key on, engine off pressure comes back up quickly after 2 cycles. Engine runs good after initial start, no stalling, no hesitation, no hard start. Throttle body, MAF sensor, IAC sensor, PVC valve have all been cleaned. Fuel filter, fuel pump, air cleaner, spark plugs replaced. This problem was not slow in developing, it happened overnight. If I open the air intake and prime with a little gasoline, it starts right away. Once started, it's ok all day until the next overnight. Any assistance would be greatly appreciated, thank you, James.
#2
RF Veteran
iTrader: (1)
Fuel pressure should hold above 50psi for a few months, not minutes, hours, days or weeks.......months
You have a returnless fuel system on an '08, so no pressure regulator, if your MPG is not way down then there could only be 2 ways pressure is dropping to 0psi.
I think the fuel filter in your model has a Return fuel line on it, so 3 connections, have a look at it.
If it does then I would replace that first, it will have a pressure valve inside, and see if pressure holds after engine is shut down.
If filter only has 2 connections, or replacing filter doesn't work, and your MPG is OK, then the fuel pumps check valve is bad, it is part of the pump not a separate piece so pump assembly will need to be replaced.
I am assuming to don't smell gas, since you didn't mention it, and that would lower MPG alot, as well as leaking injector or failed Pulse Damper
You have a returnless fuel system on an '08, so no pressure regulator, if your MPG is not way down then there could only be 2 ways pressure is dropping to 0psi.
I think the fuel filter in your model has a Return fuel line on it, so 3 connections, have a look at it.
If it does then I would replace that first, it will have a pressure valve inside, and see if pressure holds after engine is shut down.
If filter only has 2 connections, or replacing filter doesn't work, and your MPG is OK, then the fuel pumps check valve is bad, it is part of the pump not a separate piece so pump assembly will need to be replaced.
I am assuming to don't smell gas, since you didn't mention it, and that would lower MPG alot, as well as leaking injector or failed Pulse Damper
#3
Hard Start When Cold
Gentlemen, thank you for considering my request for information. I have solved the problem. It was entirely due to a malfunctioning engine coolant temperature sensor. The reason that it was difficult to pinpoint was that it was not throwing a DTC. However, after replacing said sensor, no more cold start problem. James C.
#4
RF Veteran
iTrader: (1)
Good work.
But from your description that wouldn't have been the problem of the low fuel pressure.
ECT(engine coolant temp) sensor can certainly cause issues with either cold running or warm running, as the computer uses that data to set Choke or no Choke operation.
But can't effect fuel pressure.
But from your description that wouldn't have been the problem of the low fuel pressure.
ECT(engine coolant temp) sensor can certainly cause issues with either cold running or warm running, as the computer uses that data to set Choke or no Choke operation.
But can't effect fuel pressure.
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brianr440
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01-28-2008 11:20 PM