why it's there coolant in my spark plug wells after changing thermostat? Car hasn't run since I did it. It wouldn't start, checked plugs and coolant in wells..


Asked by Sep 28, 2015 at 11:37 PM about the 2003 Pontiac Sunfire Base

Question type: Maintenance & Repair

So I changed the thermostat on 03 sunfire.
Drained system. Process said remove
exhaust manifold to access thermostat
easily. So I did so, put everything back
together, filled and bled coolant system.

5 Answers


Not trying to be a wise guy, but maybe you spilled some coolant while bleeding the system? I'd clean it up real good and see if it comes back. HTH. -Jim

2 of 2 people found this helpful.

I pulled the spark plugs out and its got coolant in it. one of the cylinders is completely full but can be seen in all 4

2 of 2 people found this helpful.

Bad hwad gasket, or a crack in the engine..

3 of 3 people found this helpful.

Correct! Bad head gasket or crack in bore/block

2 of 2 people found this helpful.

why did you change the stat in the first place . did your car over heat? did your car run before the stat work was done? it should have a ecotec motor . clean and presure test system to locate leak before you go any futher

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