"Rattling" from engine compartment

[Blitzkrieg73]

First off, hi everyone. I've read a bunch of threads here in the lead up to replacing my exhaust manifold bolts and the community is great.

Now I am here for some insight, please.

I have a rattling noise coming from the engine compartment (I think) that is most prevalent at between 1k and 1500 rpm, and usually while not applying throttle. In fact, it usually goes away when throttle is applied. I struggle to describe the noise, but my wife says it sounds like a playing card in bicycle spokes; my mind goes to one of those new years noise makers - the one that you spin around and it makes the ratcheting sound.

My first instincts are something timing chain, like a guide or tensioner, but honestly I have no idea and not sure how to check something like that.

Thanks!

 

[blue ghost]

Before getting into timing chain, check the windshield wipers to see if tight, had a similar problem on my jeep and it was the simplest of things but quite annoying. Also check it with the hood up you maybe able to find where about it may be coming from.

Good luck

 

[Ken226]

First off, hi everyone. I've read a bunch of threads here in the lead up to replacing my exhaust manifold bolts and the community is great.

Now I am here for some insight, please.

I have a rattling noise coming from the engine compartment (I think) that is most prevalent at between 1k and 1500 rpm, and usually while not applying throttle. In fact, it usually goes away when throttle is applied. I struggle to describe the noise, but my wife says it sounds like a playing card in bicycle spokes; my mind goes to one of those new years noise makers - the one that you spin around and it makes the ratcheting sound.

My first instincts are something timing chain, like a guide or tensioner, but honestly I have no idea and not sure how to check something like that.

Thanks!

The belt tensioner, idler, water pump, all can make a sound like that.

To check it, use a 3/8" breaker bar in the belt tensioner to take the tension off of the belt. While the belt is loose, wiggle the pulleys. If any move in any way other than rotation, replace it.

Checking them and replacing them in your garage or driveways is usually cheaper and more convenient that doing it on the side of the freeway after paying for an Uber to go buy the parts and tools at the AutoZone 9 exits away.

For sure the Autozone will have the part, but not the tool. You'll have to go to O'Reilly's on the opposite side of town to buy the tool.

I know this from experience.

 

[04fxdwgi]

Heat shields on the exhaust system have a habit of breaking one of the mounting tabs and can set a resonance at certain RPMs and such.

Busted cat converter core? Have you used a rubber faced hammer and started bumping things to see if anything vibrates?

 

[BenchTest]

The belt tensioner, idler, water pump, all can make a sound like that.

To check it, use a 3/8" breaker bar in the belt tensioner to take the tension off of the belt. While the belt is loose, wiggle the pulleys. If any move in any way other than rotation, replace it.

Checking them and replacing them in your garage or driveways is usually cheaper and more convenient that doing it on the side of the freeway after paying for an Uber to go buy the parts and tools at the AutoZone 9 exits away.

For sure the Autozone will have the part, but not the tool. You'll have to go to O'Reilly's on the opposite side of town to buy the tool.

I know this from experience.

I could feel the EXPERIENCE in your post.

 

[Fatbob Frank]

Make sure there isn't some foreign debris trapped under the hood too...

 

[Blitzkrieg73]

Heat shields on the exhaust system have a habit of breaking one of the mounting tabs and can set a resonance at certain RPMs and such.

Busted cat converter core? Have you used a rubber faced hammer and started bumping things to see if anything vibrates?

I got the driver side one fixed last weekend, digging into the passenger this weekend if the weather holds up. I'm hoping its that.

I'll break out the mallet and see what I can get up to. Thanks!

 

[Blitzkrieg73]

I could feel the EXPERIENCE in your post.

same

 

[Blitzkrieg73]

The belt tensioner, idler, water pump, all can make a sound like that.

To check it, use a 3/8" breaker bar in the belt tensioner to take the tension off of the belt. While the belt is loose, wiggle the pulleys. If any move in any way other than rotation, replace it.

Checking them and replacing them in your garage or driveways is usually cheaper and more convenient that doing it on the side of the freeway after paying for an Uber to go buy the parts and tools at the AutoZone 9 exits away.

For sure the Autozone will have the part, but not the tool. You'll have to go to O'Reilly's on the opposite side of town to buy the tool.

I know this from experience.

Didn't consider the pulleys, I'll give them a look.

Thanks.

 

[Burla]

You need to find out where it is coming from, front of engine or rear or side, get under there and have someone get rpm's in that range. If it is back = flexplate, sides exhaust shields, front somewhere in pully's or tensioner = probably

get a stethoscope..

 

[RamDiver]

$8.49 at HF. The picture above is mine, slightly different, same idea.

https://www.harborfreight.com/automotive/diagnostic-testing-scanning/multimeters-probes-testers/mechanics-stethoscopes.html

.

 

[Jeepwalker]

 

[Jeepwalker]

In all seriousness.....

I agree with above, you'll probably need to get the aid of a buddy/helper to give some throttle while you look around (and listen). Try to see if you can isolate it coming from the Front, VS side's or bottom. If it's when you drive, that makes it a lot tougher....

 

[Marshall]

View attachment 578127

$8.49 at HF. The picture above is mine, slightly different, same idea.

https://www.harborfreight.com/automotive/diagnostic-testing-scanning/multimeters-probes-testers/mechanics-stethoscopes.html

.

A couple ft of rubber ,plastic hose, ie gas line stuck in your ear will do the same most times , even a long screw driver will, just don't get in the fan, it makes a terrible racket .

 

[Wild one]

A couple ft of rubber ,plastic hose, ie gas line stuck in your ear will do the same most times , even a long screw driver will, just don't get in the fan, it makes a terrible racket .

The rubber hose idea works in a pinch,but i still prefer my mechanics stethoscope over either the hose or screwdriver tricks in most instances.

 

[RamDiver]

A couple ft of rubber ,plastic hose, ie gas line stuck in your ear will do the same most times , even a long screw driver will, just don't get in the fan, it makes a terrible racket .

I've used a wood dowel taped to a large plastic bottle with the bottom removed.
The setup worked perfectly to amplify that hidden noise.
It was slightly bulky and tricky to position, but it did the job.

I think I will pass on stuffing gas line into my body parts, thanks.

.

 

[Daw14]

I've used a wood dowel taped to a large plastic bottle with the bottom removed.
The setup worked perfectly to amplify that hidden noise.
It was slightly bulky and tricky to position, but it did the job.

I think I will pass on stuffing gas line into my body parts, thanks.

.

 

[Dusty]

Because of the RPM range, it could be the Cam Phaser.

Regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33-gallon fuel tank, 18” wheels. Build Date: 3 June 2018. Now at 145017 miles.

 

[Marshall]

I've used a wood dowel taped to a large plastic bottle with the bottom removed.
The setup worked perfectly to amplify that hidden noise.
It was slightly bulky and tricky to position, but it did the job.

I think I will pass on stuffing gas line into my body parts, thanks.

.

I have electronic ears now, so you may have a point,
a mic on a stick to my phone would work out quite good as they are blue tooth.
never messed with the idea. Kids & Grandkids have most of the stuff now.
I have used stethoscope .

 

[solardave2002]

I just started having the same issue. the only thing ive done is replace my K&N air filter. it only happens when im coasting (off the accerator) slow or down a small hill. i have rechecked all the clamps on the air filter, intake tubing and throttle body. all tight. i have read some where people mention give it 100-200 miles for the ECU to recalibrate the air flow (currently in process of doing this). also heard of disconnecting the battery and reconnecting and driving around for the same. it is not affecting anything, just an annoying, low rattling/whizzing noise. i'm stumped for now. will wait and see how it goes.