High pressure fuel rail sound dampining????

Jeremy Tuttle · February 17, 2018

When driving my 2016 Silverado 1500 double cab you can hear the sound from the fuel pump which is so conveniently located under the driver side door. Just curious if anyone has tried putting sound mat material to the outside bottom of the floor board to quiet this down? They use it to prevent rattles from speakers why wouldn't it cut down on the clicking sound of the fuel system.

austingta · February 17, 2018

That couldn't hurt anything, but are you sure it's not abnormal noise? I've never heard mine except the DI tick at idle.

papageoff · February 19, 2018

On 2/17/2018 at 6:28 PM, austingta said:

That couldn't hurt anything, but are you sure it's not abnormal noise? I've never heard mine except the DI tick at idle.

Not to hijack the thread, but I hear mine most of the time. I've been told it's normal, but it sounds more like valvetrain noise from the engine lugging than a fuel pump to me.

MOhunter92 · February 20, 2018

It’s so annoying. It could be the pump but I also feel like it could be the catalytic converter having something loose in it. It comes and goes when I hit bumps. A ton of GM trucks do this, Silverado, Sierra, Yukon, Tahoe. So it’s definitely a shared part causing it, I can’t stand it.

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papageoff · February 21, 2018

18 hours ago, MOhunter92 said:

It’s so annoying. It could be the pump but I also feel like it could be the catalytic converter having something loose in it. It comes and goes when I hit bumps. A ton of GM trucks do this, Silverado, Sierra, Yukon, Tahoe. So it’s definitely a shared part causing it, I can’t stand it.

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I'm not sure what that sound is. Mine is a very mechanical sound like the solid lifter valvetrain on my motorcycle. I hear it mostly under my feet on the driver's side, but my wife said she doesn't hear it on the passenger side.

Catalytic converts can have their core come loose, but that's pretty rare from what I've understood.

MOhunter92 · February 21, 2018

I'm not sure what that sound is. Mine is a very mechanical sound like the solid lifter valvetrain on my motorcycle. I hear it mostly under my feet on the driver's side, but my wife said she doesn't hear it on the passenger side.

Catalytic converts can have their core come loose, but that's pretty rare from what I've understood.

That’s where the sound comes from on the vehicles I mentioned. I don’t think it’s lifters because it only comes from the driver side footwell. It sounds like an exhaust leak to me, like what a manifold leak sounds like. I notice if I hit large bumps in the road it can make it appear or go away briefly.

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papageoff · February 21, 2018

1 minute ago, MOhunter92 said:

That’s where the sound comes from on the vehicles I mentioned. I don’t think it’s lifters because it only comes from the driver side footwell. It sounds like an exhaust leak to me, like what a manifold leak sounds like. I notice if I hit large bumps in the road it can make it appear or go away briefly.

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You know, that's a good point. I have noticed that bumps can seem to affect it.

It's nothing I'm going to sell the truck over, but I'd really like to know what the heck is actually making that noise. My neighbor thought the sound was the AC in his truck. He was convinced by the fact that his 2015's AC blew up in August last year. Of course, that didn't stop him from buying a 2017 Midnight Edition the next day. ;-) I've ruled out the AC's involvement on mine by turning it off/on to see if anything changed and other than the load, it seems the same.

It does seem to vary in volume with engine load/rpm, going away (or drowned out) after somewhere north of 2000RPM. That's why I figured it was the valvetrain noise. It's usually pretty pronounced on most engines when they're under load at low-rpm and can echo through the exhaust system.

MOhunter92 · February 21, 2018

You know, that's a good point. I have noticed that bumps can seem to affect it.

It's nothing I'm going to sell the truck over, but I'd really like to know what the heck is actually making that noise. My neighbor thought the sound was the AC in his truck. He was convinced by the fact that his 2015's AC blew up in August last year. Of course, that didn't stop him from buying a 2017 Midnight Edition the next day. ;-) I've ruled out the AC's involvement on mine by turning it off/on to see if anything changed and other than the load, it seems the same.

It does seem to vary in volume with engine load/rpm, going away (or drowned out) after somewhere north of 2000RPM. That's why I figured it was the valvetrain noise. It's usually pretty pronounced on most engines when they're under load at low-rpm and can echo through the exhaust system.

It’s very weird and it’s on all of their full size half ton trucks. I drove a ton of rental trucks during a period my truck was getting its transmission and a few other issues worked with and half of them did it. I had a 15 that didn’t do it at all and my current 16 did it non stop, then now it only does it most noticeably after bumps and it comes and goes.

Since bumps have something to do with getting the noise to happen, it limits it to most likely a pump of some sort or something loose with exhaust. It directly correlates with throttle for me, I have videos of my sound but this stupid Tapatalk won’t let me upload a video.

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MOhunter92 · February 21, 2018

let’s see if this works.

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Jeremy Tuttle · February 21, 2018

Mine is the same, it directly correlates with the fuel pedal. When I get on it the sound gets louder and at highway speeds it a dull drone. Has anybody tried tightening the exhaust bolts?

MOhunter92 · February 21, 2018

Mine is the same, it directly correlates with the fuel pedal. When I get on it the sound gets louder and at highway speeds it a dull drone. Has anybody tried tightening the exhaust bolts?

I wanted to test this but it’s so hard to get to the bolts near the catalytic converter and the bolts are also usually so tight that I don’t think I could turn them with hand tools. I think it could work though. Just a matter of what bolt and where. I also went over my exhaust as closely as I could and didn’t notice any leak, but the sound is just textbook exhaust leak to me.

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Jeremy Tuttle · February 21, 2018

I find it hard to believe that all these trucks have the same exhaust leak though.

MOhunter92 · February 21, 2018

What if it’s a bad manifold gasket, or bad clamp in the exhaust. I think it’s possible. But I really don’t know, I just am pretty confident it’s not anything with the motor, it’s a pump or fuel line or part of exhaust.

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greyjimmy · March 31, 2018

I just bought a 2015 Sierra 4x4 with the 5.3 and 60,000 miles.

At idle it sounds like an industrial sewing machine under the hood. Sometimes a light knocking as if coming from a lifter but I just had full diagnostic done by a third party and it showed nothing. They acted as if it was not an issue. It only does it after its warmed up and at idle. It's quiet otherwise. Is this typical?

Justin101714 · April 1, 2018

The noise you hear is how the exhaust is actually flowing through that converter on the left side. Mine does it, but only in V4 mode. If you touch the pedal and the engine enters V8 mode, the noise goes away. Nothing wrong with it, just an operational noise. People cry about it all the time though.