Any idea what this noise could be from my engine bay?

[Bootbox]

Lately I notice a rattle sort of noise that comes and goes, it's pretty loud at times very faint at others.

It sounds like it's coming from the front of the engine, the accessory area. If I put my head next to the grill I can hear it the loudest, but I can't nail down the area it's coming from to save my life.

It's not there when I first start the truck, 10 seconds later though it comes in full volume. The other time I notice it is when I pull into my parking spot and put 'er in park. It will be relatively quiet for a second then rattle a little more loudly, on and off like that while I idle. It might be doing it while I drive too but I'd never hear it over my exhaust to be honest.

I've checked the plugs and none are loose. I've checked for any and all leaks (exhaust and other) it's all good to go on that front, I'm thinking maybe idler or accessory pulley? What about the idler bracket, do those come loose with age?

It's an '01 with 60,000 miles on it, are there any common problems that would cause this that tend to pop up around now?

 

[INFAMOU$]

try and get a long handled screw driver and place the end on a "non turning" part of the pulleys and listen with your ear on the end of the handle... should amplify the noise to let you know which accessory is doing it.. probably bearings in one of your pulleys.

 

['88347coupe]

A/c compressor:shrug: You did say it was stoping and starting

 

[s|ck]

Might be a rod bearing going out? I was hearing a slight rattle sound at times before it went

 

[flip_86]

i've got an 01 with 15,000miles, i think i've got the same problem, my first thought was the a/c cycleing, i havn't looked into it yet, but i know my a/c wasn't on at them time, i'm not familiar with this particular a/c system but some will cycle on thier own to prevent freezeup

 

[Bootbox]

A/c compressor:shrug: You did say it was stoping and starting

I drove around today after work without the a/c on and it was still making the noise.

Might be a rod bearing going out? I was hearing a slight rattle sound at times before it went

Oh my god I hope not :cryying:
It's pretty loud and sounds like it's outside the engine honestly. I'll just keep telling myself that lol. I'll get it up to my parent's garage this weekend and poke around with my buddy's stethoscope I was just wondering if there was something that does this regularly.

 

[lightninmike]

Nice to see you seem to be doing good Rob.
Can you tell if its the supercharger making the noise?

 

[ACSVT]

Does it sound like this? This is my truck, two new idler's later the sound went away.

http://s41.photobucket.com/albums/e280/acsvt/?action=view&current=holidays002-3.flv

 

[OldTimer]

Does your truck have an aftermarket upper/lower pulley? Mine has both and it has the "rattle" sound which sounds like a can of marbles under the hood. Apparently it's pretty normal for a modded Lightning where the pulleys have been changed... maybe especially the upper.

 

[funair02]

what you are describing is very similar to what I have...

Does it sound like a diesel tap when it happens???

I think its the cam phaser

 

[Bootbox]

Nice to see you seem to be doing good Rob.
Can you tell if its the supercharger making the noise?

:beer:
It's hard to pin down, the truck (exhaust, fans etc) is so loud when it's running. When the hood is popped no matter where you put your head in the engine bay, the noise is the same volume. When you put your head down in front of the grill though it's a lot louder, seems to me that it's coming from the front of the engine, maybe the radiator/fan shroud, possibly the I/C pump?

Does your truck have an aftermarket upper/lower pulley? Mine has both and it has the "rattle" sound which sounds like a can of marbles under the hood. Apparently it's pretty normal for a modded Lightning where the pulleys have been changed... maybe especially the upper.

I have an LFP 4lb lower, stock upper. It does sound like marbles rattling very quickly, but it's a new noise just this month and I've had the pulley for years.

what you are describing is very similar to what I have...

Does it sound like a diesel tap when it happens???

I think its the cam phaser

You could say it sounds like a diesel for sure (I don't know what a cam phaser is though)

 

[lightninmike]

I dont know what a cam phaser is either Rob.... Maybe he means lash adjuster:shrug:

 

[Scuba-Matt]

Idler pulley going bad
Or the spider gear is bad in your Super Charger.