Car sizzles when I shut it off...

[Smeech]

I noticed this once before but a lot today. For a few minutes after turning off my car, I hear a sizzling noise. The A/C or defrost isn't on, so it isn't condensation... and its 70 degrees out. It sounds like its coming from inside the cats on my Mac H-pipe! Do cats tend to sizzle...? Water will come out from my tailpipes on a cold morning, but that's it... the stang's running fine... just kind of tripping me out...

EDIT: its not consistently sizzling, just sizzles here and there...

 

[streetstang03]

its the condensation from the A/C lines dripping onto the cats. dont worry..its normal

 

[Smeech]

Even if the A/C hasn't been used for a few days?

 

[02LaserRed2V]

Yeah, it freaked me out the first time. I even made a thread panicking over it lol

 

[Mossberg]

It must be normal since mine does it too.

 

[timeless2]

Sometimes what you hear is coolant still trying to flow because of heat convection. When you shut your car off, it ceases to pass coolant through normal cooling routes and the motor's heat causes pockets of coolant to rise in temp. This rise in temp varies with other coolant (which is probably close in temp to where your thermostat is configured) and tries to rise/escape. This causes a swirling or turbulent effect inside coolant lines and housings (heater core, radiator, etc). What you hear is that movement.

Don't believe me? Go SCUBA diving on a reef where there is geothermal activity and underwater geysers. You'll actually see movement and feel water movement. Pretty neat stuff.

Sorry for the long post and I am assuming you haven't hit puddles, ran the A/C, power washed the engine bay, or dumped Mountain Dew down your defroster ducts.

 

[csledd]

Just ignore the sizzle.

After I drive my car and get out and shut the door if theres been dew or rain it splashes up against my headers and sizzles. It's pretty loud too lol. It also scared me the first time, not its kinda cool sounding lol.

 

[hauoli63]

Yeah, I have the same thing. Scared me so bad, I made my husband look under the car while I shut the door a few times ... he thought it was funny!

 

[tjm73]

There's a rubber flap that can cause this sound as cabin air pressure is equalized through it when you clsoe the door. My '98 does it all the time. Nothing to worry about.

 

[hauoli63]

Mine was condensation dripping on the exhaust ... had the top down and the ac running because it was hot!

 

[SonicBlueBabe]

Yeah, it freaked me out the first time. I even made a thread panicking over it lol

LOL, I freaked out at first too, now me and my friends call it the snake under the car. Kinda sounds like a snake

 

[todd4566]

I love these kind of posts. It reminds me of just how many different sounds my car makes. I have squeeks over some bumps, the occasional sizzle when i close the door, a particular squeek when i turn right after backing up in the morning, and a rare air conditioning related "pssssssht" sound if I turn the AC on immediately after I start driving on a hot day.

 

[lgndracer]

Mine does it too. I especially notice it when I park it in the garage, get out of it, and close the door. Then I get the "sizzle".