Fuel pressure sensor- How does it work?
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Fuel pressure sensor- How does it work?
So I accidently broke this sensor. Its located on the fuel rail on the driver side. I tried to pull the vac line off of the top side of it, and the plastic nipple cracked off. I was going to just replace it, figuring its probably cheap. Until I looked it up and see its over $100 at autozone. Is this just a vaccum connection? If so Ill probably just try to get it sealed up with some silicone. What would happen if it had a small leak?
I just finished changing timing chain tensioners/guides and it started up and seemed to idle fine without it being hooked up. Although I only let it run for 30 seconds or so
http://www.autozone.com/fuel-deliver...4_709864_4995/
I just finished changing timing chain tensioners/guides and it started up and seemed to idle fine without it being hooked up. Although I only let it run for 30 seconds or so
http://www.autozone.com/fuel-deliver...4_709864_4995/
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Joined: Sep 2008
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From: Lake Mary Florida
Nope, you need it. Try a bone yard for a cheaper replacement if cost is an issue.
Ford switched to a single fuel line, rather than two; one used to be a return line to allow excessive fuel pressure to route back to the fuel tank. Two lines increased the potential of "vapor lock", so they went to a single fuel line from the fuel tank to the fuel rail(s).
That sensor eventually (by way of the PCM) informs the Fuel pressure driver module (located by the spare tire) to "turn on/turn off" the fuel pump in the gas tank, based on the pressure it detects at the fuel rail, hence its name "fuel pressure sensor". Without this fuel pressure sensor, the fuel pressure could be too low, or too high, and should eventually set a CEL, and/or poor running conditions, and/or failure to start. Engine idle does not require much in the way of fuel; once you put a load on the engine (driving), I suspect you will experience problems, and possibly the PCM will put the truck into a "limp home" condition; this forces the PCM to use a default mapping of fuel to air mixture which allows the truck to stay running, good enough to get you off the road safely. No performance in this mode. You will notice it.
Ford switched to a single fuel line, rather than two; one used to be a return line to allow excessive fuel pressure to route back to the fuel tank. Two lines increased the potential of "vapor lock", so they went to a single fuel line from the fuel tank to the fuel rail(s).
That sensor eventually (by way of the PCM) informs the Fuel pressure driver module (located by the spare tire) to "turn on/turn off" the fuel pump in the gas tank, based on the pressure it detects at the fuel rail, hence its name "fuel pressure sensor". Without this fuel pressure sensor, the fuel pressure could be too low, or too high, and should eventually set a CEL, and/or poor running conditions, and/or failure to start. Engine idle does not require much in the way of fuel; once you put a load on the engine (driving), I suspect you will experience problems, and possibly the PCM will put the truck into a "limp home" condition; this forces the PCM to use a default mapping of fuel to air mixture which allows the truck to stay running, good enough to get you off the road safely. No performance in this mode. You will notice it.
Last edited by Mod (Ret.); Jan 29, 2015 at 06:37 AM.
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From: Gretna, la
It's worth the money and changing it yourself. "Ford" shafted me for one plus a billion other things when mine went out so buy it and change it yourself. It's easy, just 2 little screws, a wire and a hose plugged in to it. IMPO well worth it !
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Thanks for the info. I can see how it would electronically measure the pressure in the rail, but whats the vacuum line doing on that sensor is what I'm wondering?
Taking somewhere to get replaced wasn't ever a question, I wouldn't do that for something so overly simple. I just have other things to buy (belt, tensioner, oil, filter, coolant) on top of the other parts I've bought this week and just didn't really want to throw another $130 at it for something that was only going to set a check engine light with no noticeable problems. I havent even driven this truck yet since I bought it, so I'm trying to spend the minimum to get it running so I can drive it and see what else it needs as far as drive ability
Taking somewhere to get replaced wasn't ever a question, I wouldn't do that for something so overly simple. I just have other things to buy (belt, tensioner, oil, filter, coolant) on top of the other parts I've bought this week and just didn't really want to throw another $130 at it for something that was only going to set a check engine light with no noticeable problems. I havent even driven this truck yet since I bought it, so I'm trying to spend the minimum to get it running so I can drive it and see what else it needs as far as drive ability
Last edited by Ford15379; Jan 29, 2015 at 01:19 PM.
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From: Gretna, la
IMO it looks like it relays to the electrical component how much fuel pressure. I just took a look at mine and that fuel line going into the sensor Jane but about 8-10. Inches long but like I said that's my .02
