Fuel Pump Issue
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Fuel Pump Issue
2001 f150 5.4 supercrew 4x4
Having an issue with my fuel pump. Somtimes the pump will not charge the line when i turn key to on position and of course will not start. i will ussualy have to turn the key off and a few times to get it to charge the line and start. The pump works fine and has never failed while the truck is running. I have driven for 3 hours straight with no failers often. This ONLY happens onn start up. Does anyone know what could cause this. I dont think it is the pump. Was wondering if maybe its the relay or an anti-theft issue.
Having an issue with my fuel pump. Somtimes the pump will not charge the line when i turn key to on position and of course will not start. i will ussualy have to turn the key off and a few times to get it to charge the line and start. The pump works fine and has never failed while the truck is running. I have driven for 3 hours straight with no failers often. This ONLY happens onn start up. Does anyone know what could cause this. I dont think it is the pump. Was wondering if maybe its the relay or an anti-theft issue.
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Joined: Jan 2013
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From: KY.
Sounds like the pump is starting to go, or the check valve is bad. If it's the check valve it's built into pump, so the fuel pump has to be replaced in either case. What's your fuel pressure? Might want to change the fuel filter if it hasn't already been done.
Last edited by JCR 56; Jan 2, 2018 at 08:48 PM.
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If you are letting it sit in on position several seconds...and it happens...the fuel pump is sticking.
When turning the key to the on position and staying there, should be able to hear the hum of the pump run and then shut off as it pressurizes the fuel rail.
If you are just turning key and giving no time for rail to pressurizee, check valve is likely leaking pressure off when not running.
You can drive it forever with slightly leaky check valve. Fix is same, replace pump. However, a 17 yr old fuel pump has a high likelihood a failure in the next few years.. and it wouldn't be uncommon to find the filter sock on the suction of it degraded already anyway, as well as a tank with crud in bottom. Replacing it before fails is one of the best things you can do from a preventive maintenance standpoint to prevent being stranded.
When turning the key to the on position and staying there, should be able to hear the hum of the pump run and then shut off as it pressurizes the fuel rail.
If you are just turning key and giving no time for rail to pressurizee, check valve is likely leaking pressure off when not running.
You can drive it forever with slightly leaky check valve. Fix is same, replace pump. However, a 17 yr old fuel pump has a high likelihood a failure in the next few years.. and it wouldn't be uncommon to find the filter sock on the suction of it degraded already anyway, as well as a tank with crud in bottom. Replacing it before fails is one of the best things you can do from a preventive maintenance standpoint to prevent being stranded.
Last edited by mbb; Jan 2, 2018 at 09:38 PM.
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Thanks for the replies! looks like I will be replacing the pump this weekend.
It just really baffles me that it only fails to charge the line when it feels like it, and when it does charge the line and starts if runs perfectly.
It just really baffles me that it only fails to charge the line when it feels like it, and when it does charge the line and starts if runs perfectly.
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Quick question is the check valve inside the actual pump or is it located somewhere on the fuel pump assembly?
