Coolant Overflow cap 98GP

I just noticed that the snap-on cap for the coolant overflow tank does not remain on the tank. Each time I open the hood, it is just lying there. Is this supposed to keep the antifreeze pressurized and is it dangerous when it does not stay in place? Should I have the entire tank and cap replaced?

The coolant reservoir is not pressurized like the rest of the cooling system. Not dangerous but I would get it replaced as soon as possible. You're better off getting the revised tank for a '99 and up which mounts to the right strut tower. There is a kit available to retrofit '97-'98 models.

Thanks BN. Is this an aftermarket or should I buy it from GM? I live in Toronto.

The kit I was referring is from an aftermarket supplier PFYC.com but the coolant reservoir is genuine GM which would be the same one from the local GM dealer. All PFYC does is provide the mounting hardware like two screws. See link below. Not sure if PFYC ships to Canada though and there may be the issue of customs duties if shipped from the U.S.

Click here (http://www.pfyc.com/pc/GP3009/GPUNDER/1999+Coolant+Tank+-+97-03+Grand+Prix.html)

Thanks for the info. Since the item cost plus shipping is almost $60.00, I think I willtry to get one from the wrecker or buy it from GM. Will post the cost when I receive it.