Guys I noticed a strange noise today on my F. I have heard this noise with the engine running but never with the engine off. It literally sounds like an A/C compressor clutch engaging and disengaging. It made the noise several times just after shutting the engine off and the delay between hearing it got longer and longer. It eventually stopped. It is my understanding that the A/C compressor doesn't even have a clutch anymore on these cars so I am a bit stumped as to what could be causing it and if it is normal.. I have never heard it make the noise before with the engine off...

Any ideas?

 

It's normal, has to do with Evap system.... prob what it is.

 

Yeah, it is in the manual. Even my Lexus RX makes funny noises after being turned off. Something to do with emissions testing, I believe.

 

My daughters Camry did it once... probably a Toyota thing.

 

There's a vacuum pump testing the evaporative emissions system. Normally it starts 4 hours after you shut the car off.

 

I’ve seen the info in the manual regarding the EVAP test but that should occur hours after the car is shut off. Something like 5 hours.

This noise was happening right after the car was shut off and it was only running for a couple of minutes as I was only pulling it out of the garage. It was also VERY loud and metallic in nature. It did it about 5 or 6 times.

 

There's a one way clutch on the alternator drive. Maybe it's not happy. Maybe the belt tensioner pulley bearings are not happy. Pretty hard to diagnose from afar. No MIL or DTCs?