4.0 SOHC first start idle 2 low

RonD · Feb 7, 2016

Original Motorcraft pump would probably be above spec, they are built really well, but expensive.

I would find where the voltage drop is, assuming battery voltage is 12.3v or higher.

There should be no noticeable voltage drop from battery to fuel pump connector.

enjr44 · Feb 7, 2016

If I remember correctly, when troubleshooting mine, the voltage was 12 vDC at the pump for the first 3 seconds after key on and then dropped a lot ((but, not to zero) when the computer removed the ground.

mred3 · Feb 7, 2016

found ground problem and fixed getting 12+ volts on #2 pin line now. Then pump shuts off with open fuel line this is really weird , then put tester light on the same circuit that was getting 12 volts from meter, but test light wont go on ? pressures up at rail then stops then no pressure then the cycle key switch and pump comes again on and stops what the heck? in other words the pump comes on and pressures up then quits engine will not stay running.

Any ideas?

mred3 · Feb 7, 2016

What sensor tells the pump to power off when pressure is up to par

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mred3 · Feb 9, 2016

So with fuel line disconnected at front of filter I turn on ignition it pumps for 2 secs then stops is this normal? shouldn't it keep going?

jetblack02 · Feb 9, 2016

Are you trying to crank the engine while watching the pump? When the key goes to power on (not crank, but ignition) it runs the pump for about a 2 or 3 seconds to prime the line. If you keep doing that same cycle, you will see the same thing over and over. Try cranking for a short period of time with line disconnected, and if it doesn't start a solid stream of fuel, it might be something else.

gw33gp · Feb 9, 2016

mred3 said:
So with fuel line disconnected at front of filter I turn on ignition it pumps for 2 secs then stops is this normal? shouldn't it keep going?

No, it should not keep going. That is a safety feature. If the engine is not running the fuel pump shuts off after about 2 to 3 seconds in the event a line or something is broken due to an accident or something else. This helps keep the fire danger minimal.

If the engine is running it will continue to pump.

mred3 · Feb 12, 2016

Bought pressure gauge kit online (Lisle 58600) says fits all fords, but there is nothing in the kit after receiving that will connect to the tiny shrader valve on fuel rail now where do I fine that adapter? seems to be nonexistent.

Flustered

mred3 · Feb 12, 2016

hope this is it just ordered it

http://www.tooltopia.com/star-74853.aspx?utm_source=google&utm_medium=cpc&utm_campaign=paid_search_google_pla&scid=scplp6828950&gclid=CjwKEAiAova1BRDS15OXjcug_FMSJACWNAKZmjZdQKaawN6_vIwLNaWSEateQAgY8ha9K9JA2b2_eBoCSEvw_wcB

mred3 · Feb 13, 2016

Got 60 lbs now after sitting a few days start then dies wont start again code p0232 shows up with p01000 ground to pcm is good on outside wire any ideas

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RonD · Feb 13, 2016

p0232 means PCM is sensing voltage on the fuel pumps 12volt wire when there shouldn't be any.

P01000 means battery was disconnected long enough for PCM to need a few Drive cycles to relearn some engine/trans controls, it can be ignored, assuming battery was disconnected or PCM was.

PCM activates Fuel Pump relay and has a wire spliced in to the 12volt out wire of that relay, when computer shuts off the relay it will expect that 12volts to go away, if it doesn't then you get p0232

When you first turn the key on the PCM will run fuel pump for 2 seconds then shut it off.
Is that happening?
Or is the fuel pump staying on after the 2 seconds?

Could be fuel pump relay has a short to ground so is coming on with the key and not going off as it should.

mred3 · Feb 13, 2016

It shuts off could be code from before

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mred3 · Feb 13, 2016

Pulled a couple of plugs i just put in before it died the other day they are blackened

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mred3 · Feb 14, 2016

Ok I thought I had a fuel problem but after finally getting a pressure tester its ok, what the truck is doing after setting a day it will start up for a few seconds and die then it wont start at all, let it set over night it will do the same also noticed it would backfire through intake like a flooded carbureted motor would do. haven't had it running long enough to gather any new codes right now it showing P0232 & P1000 also pulled a couple of spark plugs they are black. This is driving me nuts

Could it be the remanufactured injectors causing this? I guess I could put originals back in. Wound be no fun at all.

I also installed new crank & cam sensors which I was going to do anyway since they were original.

RonD · Feb 14, 2016

Try the Clear Flooded Engine test, to see if fuel injectors are the problem
Turn key on
Press gas pedal to the floor and hold it down(this turns off fuel injector pulses from computer, spark stays on)
Try to start engine

Engine shouldn't start as long as gas pedal is held down all the way
It shouldn't even fire a little, no fuel should be getting into the intake manifold

Clear Flooded Engine routine is when the computer sees 0 RPMs and above 4.5volts from TPS(throttle position sensor), this is wide open throttle voltage, it will then shut off injector pulses.
So this depends on TPS working as it should, of course.

If engine starts then when it's above 400 RPMs computer will exit Clear Flooded Engine routine, or if you release the gas pedal.

There are two ways fuel can get into the intake, leaking fuel injector, or Pulse Damper vacuum hose.
Either should show loss of fuel pressure when key is off.

If possible have fuel pressure gauge hooked up when you start the engine, if pressure drops as engine dies then either fuel pump power is being cut or fuel line is partially blocked, fuel is being used up and it takes awhile for more fuel to flow past the blockage, which is why it restarts after sitting awhile.
Could be bad fuel filter or connector

4.0 SOHC first start idle 2 low

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