2012 2.7L engine tick with AC

Hi everyone,

I just bought a 2012 Tacoma off my dad, the original owner. It’s a 2.7L. I have a strange tick/chirp that seems to be tied to the use of AC, however the compressor itself is totally quiet.

I used my mechanics stethoscope all over the engine bay. It’s louder on the passenger side for sure, right Uber the exhaust/engine.

At first the only spot I could hear it clearly was on the exhaust shield. Doesn’t make sense... then I poked around under that little plastic intake cover thing and it seemed louder there.

When I shut off the AC it seems to go away entirely. It might be there occasionally but I’m so hyper focused on it I’m not really sure. I can hear it at idle inside the cab, but not while driving.

I checked all the pulleys, no sign of noise.

Truck was always serviced at the dealer. Oil changes done every 5-7k kilometers (I’m in Canada), along with general servicing about 2-3 times a year. My dad is a very conservative driver so it was never abused.

The dealer just had it in their shop for an oil change and inspection, they didn’t flag it. Is this a normal Toyota thing, or do I need to hunt this down?

 

Here is a video. Sound is most pronounced at 18 seconds.

https://youtu.be/GaWTIhJlNnE

 

I think I’ll revise my description. The tick is there without the Ac on but much quieter. When the idle sits down around 500rpm or whatever, it’s basically silent. I think when the idle jumps a touch with the Ac compressor that’s when it’s more pronounced.

 

Anyone care to take a stab at this? It definitely happens even with the AC and blower motor turned off. Seems to be either related to a valve or exhaust leak maybe, but I'm not sure this sound fits with that guess

 

It's a 4 banger, and they do sound like a sewing machine. Check your power steering fluid too. I've always used 5-20, not the 0-20.

 

I'll have a look. I can hear the sound of the valves tapping, I quite like that sound honestly. It's the chirpy-tick I'm perplexed by. I have found a few videos of other trucks on youtube with the same sound though.

 

Power steering fluid good. The tick isn't anywhere near the pump either. It's right above the air switching valve, under the air cover.

 

Enjoy the truck and stop tracking noises. If you are overly concerned do a used oil analysis.

 

Mine has sounded like that for over 9 years and stick to 0/20 motor oil

 

Sounded pretty normal to me

 

I have a 2.7L and it sounds normal to me on the video. Keep in mind that this is a big displacement 4 cyl and it resembles a diesel engine at idle and not a purring 2.0L Honda Civic. 2.7L is too big to be a 4 cyl and it shows that with its coarseness. 20 years ago 2.0L was generally considered the limit for a 4 cyl but they kept growing as vehicles got heavier.

Saying that, I had an issue where the heat shield on the catalytic converter came partly loose and rattled. Twice. First it was two of the fasteners that rusted away, then a few years later it was the clamp.

 

With it running pore water on the belt see if it goes away. If so its a belt or pulley for sure.