Okay, so my parents 88 GP SE is having problems starting up. This usually only happens when it gets colder, like -15 degrees Celsius or below.

It starts up absolutely fine whenever its warmer out. But as soon as it gets colder, it will turn over and try to start and will even start but then 2 seconds after it starts it will stall. Sometimes it won't even start at all just turn over. Regardless if it starts or not, it always smells like raw gas in the exhaust. Sometimes if my parents floor the gas pedal it will start, sometimes it won't help, but again, it stinks like raw gas.

My dad did an oil change on it and put methyl hydrate in it the last time it did this when it got cold, that seemed to have made the problem go away. But it has started again. They put some more methyl hydrate in it, and it seems to have helped. It has never needed methyl hydrate before.

This car has probably needed to have a couple major services since they bought it, would this maybe have something to do with not having it done? And if not what could this be?