Passenger side Bubbling/Boiling noise after shutting off engine.

Jackie_Moon

Member
Joined
May 3, 2021
Posts
11
Reaction score
0
Location
Michigan
I'm experiencing a boiling/bubbling noise from the passenger side when I shut the engine off after I drive the vehicle to normal operating temps. It hasn't overheated. It doesn't run weird (except for idle, but i'm pretty sure that's stemming from my P0401 code).

Thoughts?
 

99WhiteC5Coupe

Full Access Members
Joined
Jun 3, 2015
Posts
1,434
Reaction score
618
Location
USA
I'm experiencing a boiling/bubbling noise from the passenger side when I shut the engine off after I drive the vehicle to normal operating temps. It hasn't overheated. It doesn't run weird (except for idle, but i'm pretty sure that's stemming from my P0401 code).

Thoughts?


The noise is a sign of air in the coolant system. In addition to checking the coolant reservoir, check the radiator to ensure it is full when cold.

You may have a small coolant leak, and a problem with the clamps or hose on the coolant reservoir, which would permit the coolant system to pull air into it when the engine cools down (although coolant remains in the reservoir).
 

Don Hall

Full Access Members
Joined
Jun 8, 2018
Posts
520
Reaction score
159
Location
SANTA CRUZ, CA
Boiling water in the overflow bottle can be caused by a ruptured head gasket, allowing exhaust gases into the cooling system. But, you are not experiencing over-heating, which would be the case if the gasket was ruptured.

As my C5 Corvette friend suggested, check to see if a siphon is occurring during cool-down. The coolant in the over-flow bottle should be above the fill mark when hot, and lower when cold. If the coolant isn't flowing back to the radiator, there is a breach in the closed system allowing air into the system.

Without a siphon, you will keep losing coolant, and eventually over-heat.

If air is entering the coolant, you can pressurize the system to locate a leak using a loaner tool from most auto stores that fits over the cap neck of the radiator.

Also, check the gasket on the rad cap for deformity. A common problem.
 
Last edited:

Jackie_Moon

Member
Joined
May 3, 2021
Posts
11
Reaction score
0
Location
Michigan
Well..... i was a *******.

You told me to get it checked out. My father told me to not create a problem if it isn't there. i foolishly listened to my father. My expy overheated and could barely limp me home.

Is there anything i can do to stave off an engine replacement?
 

00XTL

Well-Known Member
Joined
Mar 2, 2014
Posts
98
Reaction score
44
Location
North Carolina
Ive had this happen to me. I flushed my heater core and got all the debris out from over the years and it fixed the issue until more debris gets in there.
 

Jackie_Moon

Member
Joined
May 3, 2021
Posts
11
Reaction score
0
Location
Michigan
Update: it was just a blown belt. overheated, but i threw a new belt on and it's running fine. Thanks for the heater core tip, i'll look into that

I should address a few of the replies.

I believe my head gaskets are fine. Normal operating temperatures, power, noise, exhaust etc.

My coolant reservoir is located on the driver's side, opposite the location of the noise. Level of coolant has remained consistent, although it has developed a slightly black-grey hue to the normally bright green color. Is this oil in the coolant system, or debris from radiator, hoses, etc? I have limited mechanical knowledge.
 
Last edited:
Top