tapping noise from under hood

[Erin]

I'm stumped. I've had a tapping noise coming from under the hood for years. Until this year it only happened during the colder months, but now it always happens. I had a lifter adjusted recently but the noise is still there. 4 different mechanics cannot tell me what it is. The noise starts out loud then quiets some as the engine heats up but is still audible. Any help is appreciated.

Erin

 

[skylark]

I'm stumped. I've had a tapping noise coming from under the hood for years. Until this year it only happened during the colder months, but now it always happens. I had a lifter adjusted recently but the noise is still there. 4 different mechanics cannot tell me what it is. The noise starts out loud then quiets some as the engine heats up but is still audible. Any help is appreciated.

Erin

Can you get a video of it for us? My best guess off the top of my head without having any more of a description than what you gave us would be piston slap. It is more common in the vortec engines than it is in the TBI engines.

 

[Erin]

I'll try my best. The engine is a 5.7 liter crate engine that's only 5 years old and around 20,000 miles on it. I do get code 32(EGR) code sometimes. The EGR valve was replaced about 2 years ago and the EGR solenoid was replaced 2 months ago.

 

[Supercharged111]

You still haven't clarified TBI or Vortec, stock or otherwise. Please provide more details.

 

[Erin]

It’s TBI stock. My phone is being stupid and I can't upload the videos. As soon as i get my camera ready i'll try that route.

 

[Supercharged111]

When you say crate, who built it?

 

[Erin]

I bought it from O’reilly auto parts. I don’t know who builds their crate engines.

 

[Supercharged111]

In that case, I wouldn't put any stock in the 20k miles. We can troubleshot like a high mileage engine. Post a video so we can decide if it's lifters or bearings.

 

[Erin]

I'm sorry I can't get the videos uploaded. I'm not computer savy enough to figure it out.

 

[1BigCarrot]

I'd vote lifters, they can be noisy as hell when knackered.