coolant tank is overheating and bubbling after you park it

you might have a bad head gasket. you can test it yourself. get a combustion leak test kit from your auto parts store and then follow the instructions on the package, or watch a you tube vid on how to do it. it is a pretty conclusive test. If you don't want to tackle it, a lot of mechanics have equipment to sniff the system. the do it yourself kit is about 40 bucks.

yes head gasket is my vote .....//is it a 2.7 ??

Could it be the thermostat

i do not think its head gasket everything is work fine gauges are good . temp gauge normal ,car drives normal. change radiator and thermosat and it stop for awhile . it only bubbles up after i park car after driving it. had engine, water pump replaced about 6 months ago. in the summer had no problem now its cold outside this problem . thanks for your advise its anything else that can be cause the problem.

i am sorry engine is a 3.5 mopar john

my cousin had a 300 with the same issue you are having and was only doing it in his parking spot at work ...after trying to get it to do it and testing everything else we put the block tester on it and it was a head gasket ...I would either buy the kit or bring it to a shop and have them test it this way you can rule it out for sure

thanks for the advise moparjohn

The mentioned test is a good starting point. Another test you can try is let the engine cool all the way down then remove the radiator cap then start the engine and watch for bubbles. If you get bubbles right away it is the head gasket or a cracked head if no bubbles right away still could be head or gasket, but less likely.

Hey i found out what was wrong simple fix the cap on fill tank needed to be replaced. I believe it has a pressure fitting that opens and closes change cap havent had problem sense.Maybe help for anybody else that have a 2002 300m.

Cameron im having the same issue the resovor cap needs to b replaced but also looks like my whole resovor is leaking air from the ring around where u put the radiation cap bak on did u have to bleed it after u put that resovor cap?

yeah you have to bleed system there is a bleed valve in the system.

I have a 2000 Chrysler 300m and it does the same thing.boils after I parkk.heat gauge didn't go to hot until today

SOLVED my issue. Check it out guys . Have a 2006 Chrysler 300. Everything in the cooling system has been replaced... fans, fan relays and sensor. Thermostat, water pump (timing belt), radiator cap. Compression 210psi on all 6 cyl. Still had the issue would drive a a few miles after it hit normal running temp . Then it would just spike up below the red and fast. I would pull over. it would be boiling out the reservoir and I would loosen the bleeder valve and air would just come out when I flipped up the red tab on my radiator cap coolant would start to come out the bleeder valve. Anyways had me stumped. Got to thinking about and I came up it seems at some point the air in the reservoir would go into the block and the coolant into the reservoir. To teat my theory I took a pair on mini channel lockes and pinched the top reservoir hose closed. And the overheating issue I was having is now over. Hope this helps

Jason coley can you be more specific about which hose it was ? The one coming from the reservoir cap area or the one on the actual top left side of the reservoir? and maybe more steps about how you did the process?Pictures would be great.

Had this issue, and it turns out ti was just the coolant cap