GenVibe - Community for Pontiac Vibe Enthusiasts

Is this normal? I always hear this hissing noise underneath the rear of my bumper somewhere by the muffler while the car is parked, engine off.

This usually happens approximately 5 hours after I have parked in the garage where it is quiet.

The hissing sound lasts about a minute then shuts off.

Is there something electrical there by the muffler? Some kind of gas evaporator or something? I went underneath and can't pin point where the sound is coming from.

Ok, the sound is more like a small air compressor motor sound than hissing but not as loud.

I think your car is infested with a nest of Vibe Vipers! Or more likely this: Purge pump.
https://www.youtube.com/watch?v=9EREwCYvX5c

Totally normal. It's the EVAP system testing itself.

Chiadog wrote:I think your car is infested with a nest of Vibe Vipers! Or more likely this: Purge pump.
https://www.youtube.com/watch?v=9EREwCYvX5c

Thanks for the info! Did a lot of searching over the interwebs and nothing. "Purge pump" was the keyword I needed.

gtv237 wrote:Totally normal. It's the EVAP system testing itself.

Good to know, thanks. I was about to dismantle the under carriage and look for a gps tracking device