2016 hybrid highlander exhaust burbling mystery


Hi Scotty and team, and fellow internet friends,

I need help with figuring out why the gas/hybrid engine under load, like starting from stop, or accelerating in low gears is making a loud than comfortable burbling noise coming out of the tailpipe. Along with vibrations that are worse in colder weather.

It always happens when the gas engine is on and under load on lower gears.
Multiple Toyota techs haven't been able to find anything. No check engine lights.

Exhaust part that has the main muffler and cat in one piece seems free of any cracks. Visually solid. Specialty muffler places are scratching their heads. I changed the rear resonator, no cigar. Transmission fluid, no difference.

Most say it's the engine: "its just like this". Really? For a 2016?
Its loud inside even with the windows closed. And in the winter month it works even harder that makes the instruments rattle.

Bought the suv a year ago and its been like like this. No CELs. Bought it at 77K kms (47K miles) and its at just under 100K kms (60K miles) now. Had someone inspect the body too to verify accidents free carfax.

No other issues on this. Love the car otherwise, would like to keep it for as long as I can.


Comments (2)
No. 1-2

Seafoam is my goto for fuel injector cleanup. I'll pop one in the tank.
Ignition coils.. spark plugs.. hmm I'll see what the manufacturers range is on them. Happy to change them to get my sanity back now at any cost really. Including spending 2K on a new muffler even if I have to go to my retirement savings! :P

Scotty Kilmer
Scotty Kilmer


Hybrid cars can be a pain in the butt to work on. But it burbles it means the Gasoline and gin is not running right. Such act things like spark plugs Ignition coils and dirty fuel injectors