1997 F150 fuel pressure problem
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1997 F150 fuel pressure problem
I find after 3-4 hours I have to pump the gas when I start the engine, also got 100klms (23liters)dealer says with a smile "we can change the fuel pump for 800$ without even looking at it."
Wonder if that really is the problem, anybody out there think different?
P.S.
Just changed both cat converters, cleaned MAF sensor and IAC.
Wonder if that really is the problem, anybody out there think different?
P.S.
Just changed both cat converters, cleaned MAF sensor and IAC.
Lead Driver
Joined: Sep 2006
Posts: 7,907
Likes: 143
There is a large lack of knowledge being displayed.
Pumping the throttle does not provide fuel to the motor like a carburator would do.
Fuel injection is fuel supplied to the injectors under electric pulsewidth control from the computer, during cranking..
At this pont you need to better define how the problem presents it'self.
What 'would' happen during a cranking attempt if the throttle were held full open is the fuel will be "shut off" by design.
This is a feature to allow a flooded motor to be cleared with air pass through only.
What do you have for an issue?
Is it a flooding issue?
Is it lack of fuel?
IAC not functioning? Poor idle control.
What is the fuel pressure?
What does the fuel pressure do with the engine stopped and just operating the ignition key to run? Doing this runs the fuel pump about 1 second to pre-prime the rails. At crankover the fuel pump turns back on full time.
If the pressure is low, an extended crank time can result.
Are there any codes set?
Good luck.
Pumping the throttle does not provide fuel to the motor like a carburator would do.
Fuel injection is fuel supplied to the injectors under electric pulsewidth control from the computer, during cranking..
At this pont you need to better define how the problem presents it'self.
What 'would' happen during a cranking attempt if the throttle were held full open is the fuel will be "shut off" by design.
This is a feature to allow a flooded motor to be cleared with air pass through only.
What do you have for an issue?
Is it a flooding issue?
Is it lack of fuel?
IAC not functioning? Poor idle control.
What is the fuel pressure?
What does the fuel pressure do with the engine stopped and just operating the ignition key to run? Doing this runs the fuel pump about 1 second to pre-prime the rails. At crankover the fuel pump turns back on full time.
If the pressure is low, an extended crank time can result.
Are there any codes set?
Good luck.
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New User
Joined: Oct 2011
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thanks
I do not smell overflow of fuel. No "check engine light"
As I stated, it happens after the truck sits overnight or 4 hours or more, which is weird.
Can it be a clogged fuel filter? or a bad ECU?
tring to narrow it down before the gready dealer gets a stab at it.....again thanks for your help[
As I stated, it happens after the truck sits overnight or 4 hours or more, which is weird.
Can it be a clogged fuel filter? or a bad ECU?
tring to narrow it down before the gready dealer gets a stab at it.....again thanks for your help[
Lead Driver
Joined: Sep 2006
Posts: 7,907
Likes: 143
Put a fuel pressure gage on the port.
Turn the key to run one time.
What does the pressure reading say?
If no or very low pressure like a few lbs., there is a fuel line/pump issue.
Do this several times.
Does the fuel pressure build to at least 35 psi?
If yes, the engine will start on that pressure.
If no, hard starting will likely result.
No/low pressure can be a leaking injector, plugged fuel filter, faulty fuel pump or the relay that feeds power to it is causing a voltage feed issue or even a faulty regulator.
Part of the high cost of dealer service is they have to check out the same items as you and you pay the labor and parts charges.
Nothing wrong with dealer service.
They have overhead to pay for, you don't have, if you don't want to do the work.
Need a little perspective on it to be fair.
Good luck.
Turn the key to run one time.
What does the pressure reading say?
If no or very low pressure like a few lbs., there is a fuel line/pump issue.
Do this several times.
Does the fuel pressure build to at least 35 psi?
If yes, the engine will start on that pressure.
If no, hard starting will likely result.
No/low pressure can be a leaking injector, plugged fuel filter, faulty fuel pump or the relay that feeds power to it is causing a voltage feed issue or even a faulty regulator.
Part of the high cost of dealer service is they have to check out the same items as you and you pay the labor and parts charges.
Nothing wrong with dealer service.
They have overhead to pay for, you don't have, if you don't want to do the work.
Need a little perspective on it to be fair.
Good luck.
many thanks
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