2011 Tahoe Chirping Noise Engine Area

[GreaseMonkey4x4]

My wife and I purchased a 2011 Tahoe back in April with about 7,000 miles on it. Over the past few months, there is an intermittent chirping noise on start-up that will last about 30 seconds and go away. Usually seems to occur on a cold start, but not every time.

A similar noise also occurs in high gear high load situations. For example, cruising at 35 MPH if you ease into the throttle enough without the transmission downshifting, a muffled chirping noise is heard from the engine bay area. It sounds very similar to an HVAC blower motor going bad or loose belt tensioner. If you brake torque the truck and get the RPMs up around 1500-1700 the noise can be heard as well. It's faint but definitely noticeable.

I've had it to two different dealers. One couldn't confirm the noise even though I've had two techs ride along who both heard it, and the other that confirmed the noise but said it is normal. They had another 2011 Tahoe on the lot and supposedly heard the noise in that one as well. One dealer put a new belt on it, which didn't change the noise at all, and then replaced the alternator which also didn't improve the noise.

It has gotten worse over the past couple weeks, and I'm still stumped. I'm curious if anyone else has had this issue and what was replaced to fix it.

 

[dddsnapon69]

your in michigan and a dealer can't diagnose this. If the rpm at which the chirping is the "same" whether on cold start or higher speeds so in park and in say 5th or 6th gear and you can drive in or out of the rpm of the noise then it is the camshaft.
Cylinders can be cancelled to pinpoint which one, but to do so you need to push on each rocker arm running in the rpm range.

 

[skeith223]

Mine did that the top belt tensioner was replaced and it went away they are very problematic from canada