Exhaust noise?

[Springbubba]

I fired my truck up the past couple of days first thing in the morning, 32 deg F (the temp is not abnormal, but I included it for reference). Started great as always, but right after it started up, at idle, while it seemed to be running fine, a loud howling noise was coming from the exhaust. I was outside the truck, so I hopped up in it, tapped the gas, and the noise immediately went away and did not return all throughout the day.

It sounded to me like air blowing out the end of a large compressor hose.

I am new to diesels, and this site, and have learned much already, but I have no clue what this could be. I installed the air intake last weekend (I read about how much people around here dislike K and N a little to late), and the programmer last night, which I am in love with.

Any thoughts? I really appreciate it.

 

[White Buffalo]

Not sure about the noise, but it sounds normal to me with a 4" exhaust.

I would definitley reconsider your air intake system or at least get an oil analysis done from a place like www.blackstone-labs.com ($20). The silicone reading will show how well your Air Intake System is filtering. The reason most folks dislike K & N's for the 7.3L motor is because any filter media of this type can allow the larger dust particles through and dust your turbo over time (not good and lots of $). As you know diesels need a ton of good clean air. Some folks have been successful with the K & N but an oil analysis is the only way to be sure it is keeping up to par.

Not nocking K & N, used them on my Harleys & cars but for diesels it's not the best choice.

 

[Tbar]

The noise you are hearing is the exhaust back pressure valve that closes to help warm up the engine faster. It is normal.


Tbar

 

[Wingdog]

The noise you are hearing is the exhaust back pressure valve that closes to help warm up the engine faster. It is normal.


Tbar

I second that, happens always in the cold weather.

 

[BIG JOE]

The noise you are hearing is the exhaust back pressure valve that closes to help warm up the engine faster. It is normal.


Tbar

I third that. What Tbar & Wingdog sez. The EBPV, do'n what it's sposta do.

Joe

 

[Springbubba]

Thanks!

Thats a relief. Thank you guys.