Driving home from work tonight, started to hear a faint grinding/rattling noise from what sounded like under the dash somewhere. Turned everything off (radio, A/C, etc.) - no change. Got home, pulled in the driveway, opened the hood, and it sounded like it was coming from the back side of the intake manifold, by the firewall. Puzzled, I took off the engine top 'beauty' cover and figured out it seemed to be coming from the fuel lines. Put the truck up on ramps, slid under half expecting to trace the noise back to the fuel pump (pump bearings going bad? noise carrying up the lines?), but instead, the noise seems to be centered on the Flex Fuel sensor... or at least that general area. Problem is the noise follows along all of the fuel lines, so it's more of locating the noise by touch than by ear. Scooted back to the fuel tank area and its pretty quiet back there.
So, the noise is definitely coming from that area right behind the rear cats... right about where the fuel sensor is. A year or 2 ago, when Rich had my truck in his shop for other work, he pointed out a small hairline crack in the flex fuel sensor. Now it's a bigger crack as you can see in the video. I don't have much experience with flex fuel sensors going bad -- is this what they sound like? Not sure what would be making the grinding/rattling noise though if it's just a simple passive fuel sensor...? Damn sensor is like $400 online - more at a shop, I'm sure. Probably needs to be replaced regardless -- but was curious if you guys think it's the FF sensor causing the noise, or something else (pump, etc.)?
The truck is not throwing any DTCs.
Is there any easy way to confirm its the FF sensor making the noise? e.g. If I pull the wiring harness plug out of the FF sensor, would I expect that grinding/rattling noise to stop?
So, the noise is definitely coming from that area right behind the rear cats... right about where the fuel sensor is. A year or 2 ago, when Rich had my truck in his shop for other work, he pointed out a small hairline crack in the flex fuel sensor. Now it's a bigger crack as you can see in the video. I don't have much experience with flex fuel sensors going bad -- is this what they sound like? Not sure what would be making the grinding/rattling noise though if it's just a simple passive fuel sensor...? Damn sensor is like $400 online - more at a shop, I'm sure. Probably needs to be replaced regardless -- but was curious if you guys think it's the FF sensor causing the noise, or something else (pump, etc.)?
The truck is not throwing any DTCs.
Is there any easy way to confirm its the FF sensor making the noise? e.g. If I pull the wiring harness plug out of the FF sensor, would I expect that grinding/rattling noise to stop?
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