Ping, Ping, Ping sound after turning car off, possible from exhaust manifold?

[Judge2]

Any ideas on what I might be facing.

After turning the car off, I get a ping, ping, ping, ping type sounds from the engine. listening with a mechanic stethoscope makes me think its coming from the exhaust manifold area.

Does this suggest something is cracked?

[matt1mzfe]

If the engine is hot the exhaust manifold heas shield gets very hot and as soon as the flow of hot exhaust stops the manifold and heat shield begin to cool and contract as they do so. The thin steel heat shield cools much faster than the thick cast iron block & exhaust so it contracts much faster and moves where it is bolted on to the block making a creaking sound.

My car does this after a longish drive, I have no leak / crack... it runs perfectly. I would be very hesitant to believe a mechanic who is trying to tell you there is a problem just because of this sound when the car is turned off.

Does it sound and drive ok when turned on - if yes then don't let the mechanic fool you into paying - he will most likley take the heat shield off (a few bolts) put some high temp pearing grease on the bolts... and refit it. Then tell a story and charge you a lot.

I would be asking myself how much I trust this particular mechanic too.

[TedL]

Originally Posted by Judge2

Any ideas on what I might be facing.

After turning the car off, I get a ping, ping, ping, ping type sounds from the engine. listening with a mechanic stethoscope makes me think its coming from the exhaust manifold area.

Does this suggest something is cracked?

Is this your first car? Every car I've owned in the last 25 years has made that sound. As noted above, it's from the thin metal heat shields as they cool.

[ghettosled]

second that - pinging from a hot cat when it starts to cool is normal.

[BMR]

Yup, totally normal. Every car I've ever had did it.

[nevada]

Originally Posted by matt1mzfe

If the engine is hot the exhaust manifold heas shield gets very hot and as soon as the flow of hot exhaust stops the manifold and heat shield begin to cool and contract as they do so. The thin steel heat shield cools much faster than the thick cast iron block & exhaust so it contracts much faster and moves where it is bolted on to the block making a creaking sound.

My car does this after a longish drive, I have no leak / crack... it runs perfectly. I would be very hesitant to believe a mechanic who is trying to tell you there is a problem just because of this sound when the car is turned off.

Does it sound and drive ok when turned on - if yes then don't let the mechanic fool you into paying - he will most likley take the heat shield off (a few bolts) put some high temp pearing grease on the bolts... and refit it. Then tell a story and charge you a lot.

I would be asking myself how much I trust this particular mechanic too.

what mechanic? he didnt say anything about that.
he said HE listened to it with a stethoscope...