Irregular metallic tap sometimes when cold start

[proffittmarke]

My 2022 GMC Sierra Limited 5.3L L84 141,000 miles has an irregular metallic tap sometimes on a cold start. It goes away in 3-5 minutes. Any idea what it could be?

Listen below:
Tapping noise

 

[charbaby]

Lifters? Hard to tell!

 

[MParr]

Lifters or exhaust leak?

 

[JavierH19]

It's an inconsistent rhythm unlike the one in dirty lifters or a exhaust leak which have a pretty consistent rhythm. I wonder If it's intake that are known to tap inconsistently sometimes i think they're called imrc and i think these newer trucks have them. Possibly a purge valve not working that well. Though even slightly loose spark plugs are known to make a low tap sound but still run fine but i don't think it's this. I've also heard of a bad intake gasket causing this. I think it's intake related.

 

[Donald]

Probably lifters. A mechanics stethoscope might help. Not an expensive tool and works better than you think

 

[Arc]

Use a Short piece of pipe up to your ear and locate the area of the noise.

 

[Donald]

When I first read this I said I have never heard of an irregular metal tap. They are always the exact thread size.

 

[Kira]

Depending on the temps, I'd try a thicker oil (a 10W-40?) just to see if it changes tone.

The video had me thinking parts more beefy than valves are talking.

 

[MParr]

Probably lifters. A mechanics stethoscope might help. Not an expensive tool and works better than you think

A piece of heater hose or fuel line will work.

 

[BrendanC]

sounds like a lifter to me.

I would run a few rounds of Valvoline Restore and Protect 5w-30 with a good quality filter; carquest premium, microgard select etc and see if it doesn’t improve

 

[proffittmarke]

My 2022 GMC Sierra Limited 5.3L L84 141,000 miles has an irregular metallic tap sometimes on a cold start. It goes away in 3-5 minutes. Any idea what it could be?

Listen below:
Tapping noise

ISSUE -

Irregular metallic tap with cold start immediately after engine idles down below 1,000 RPM in Park. Lasts 3-4 minutes then goes away. Seems to be on passenger side of engine.
__________
FIXES -

1st Try -

1. Cleaned throttle body & intake valves
2. Added Startron to 91 no ethanol gas
3. Oil change to Amsoil 0W-30, Amsoil filter
4. Unplugged battery 1 hour
5. Cleaned and re-oiled K&N air filter
6. Cleaned MAF sensor

RESULT: No improvement 2000 miles later
__________
2nd Try-

1. Added Hot Shots Tick Fix+Protect
2. Put on K&N high flow oil filter

RESULT: No improvement 400 miles later
__________
3rd Try -

1. Added Gunk Engine Flush, ran 5 mins.
2. Changed oil Quaker State 0w20, AC Delco filter
3. Added Dura Lube 1 quart
4. Added can Gunk Tune-up to gas

RESULT: Full improvement 100 miles later

 

[proffittmarke]

I wonder if I had a stuck lifter that freed up?