My 1995 Camaro Z28 is making some noise from the engine bay once the car is at warmed up. Attached is a video of the noise. Oil pressure is at 20 psi at hot idle. Car has about 120k miles on it. H/C/I added within the last 3k miles. I'm wondering if the noise is something loose somewhere or internal in the motor. Noise seems to be coming from the front of the motor. Any advice is appreciated.

 

Are we talking about the faint, medium-high pitched tapping noise that’s off-cadence, a bit like a woodpecker?

If so: doesn’t sound like internal engine to me, but from the video I couldn’t say what it is. Your best bet now is to narrow down the location of the sound. This can be done by ear, but the best tool is an automotive stethoscope. You can also use a long screwdriver — hold the metal end against part of the engine, and put your ear against the handle. Keep moving the tip of the screwdriver around until you find a spot where the noise is loudest and clearest.

Since the noise sounds like it’s coming from the front of the engine, I’d focus your initial attention on the accessories. If you can narrow it down to one, pop the serpentine belt off and check the pulleys and mounting brackets for wobbles.

Oh, and be mindful of loose clothing (or long hair, if that’s a thing for you) while you look for the source of the sound with the engine running!

 

Thanks for responding back to me. I've tried to use an automotive stethoscope to track down the noise and I haven't had any luck. I pulled the serpentine belt off the car and the noise is still there. Is there anything else around the front of the engine that you can think of that I could check that could be making the noise?

 

Sounds like the beginning of a rod knock to me. What does it sound like when you give it a couple of light revs?

 

The noise doesn't get worse when I rev it, the rev just seems to drown out the noise. I wish I could take a video of it, but the car is tucked away in storage.

 

I wonder if it's the harmonic balancer/crank pulley. Reason I say that is because I had one go bad on an LB9/305 in a third gen. Sounded like the beginning of a rod knock. They're sandwiched together with plastic/rubber to quiet any vibration and when that stuff gets brittle or fails, it doesn't sound good. Visually, all I could see was the crank pulley spinning. Replacing it made all the difference in the world.

 

If the balancer, I bet taking the belt off would change the noise.

 

Now that you say that, It did look to me like the balancer was a little wobbly on the engine at Idle. Wish I had taken a video of it. I will look into it a little more when I get the car out again. Is the ATI Superdamper worth the upgrade it the harmonic balancer needs replacing?

 

ATI is a quality product. It is more beneficial for built motors that spin a higher RPM than stock.

With that said I would deal with the "why" there is a noise before spending the $ on a ATI.

Removing belt would indicate the noise source is not an accessory if it still continues

Did you go with a double roller chain on the H/C/I build??

FWIW I had a rotor screw come out and bounce around inside the opti...sounded like a rod knock.

From this side of the interweb...your noise sounds "internal" engine

I would carefully use the stethoscope from under the car to see if you can isolate the sound to a specific area of the rotating assembly (read rod bearing location 1-8)

If it was a 383 build it sounds like the #2 rod bolt "slightly" hitting the oil pan