Dear Tom and Ray:

I'm a female, age 62, and I learn a lot of things from your articles. I have a 1991 Plymouth Acclaim with 20,000 miles on it. We purchased the car as a demo in July, 1991. At the time it had 13,000 miles. This past weekend, as I was returning from a long trip, the heater core burst. I did not know what had happened but was close to a full service gas station (this was on Sunday). The mechanic by-passed the heater core so I could make it home. The dealer says it is not covered under warranty. The mechanic who did the by-pass said it was very unusual to have the heater core burst in a car that new. Others said the same. What is your opinion? What causes the heater core to go bad? Your explanations are always to the point and very easy to understand.
Patsy

TOM: Well, Patsy, there's a slight chance that if you had something like a bad head gasket, it could have caused excessive cooling system pressure, and could have blown out the system's weakest link, which is the heater core.

RAY: But more likely, the heater core that your car came with was just cheap junk. How?os that for "to the point?" The mechanic who did the triple by-pass operation is absolutely right. The heater core shouldn?ot burst on a car as new as yours. And the most likely reason it would burst at 20,000 is because there was something wrong with it to begin with.

TOM: The heater core is just like a small radiator under the dashboard. Hot coolant from the engine flows through it, and when you turn on "the heat," that's where the heat comes from.

RAY: On older cars, the heater core can eventually corrode and start to leak. But it's very unusual for that to happen before 60 or 80 thousand miles at the earliest. Many cars never need it replaced.

TOM: I'd get in touch with Chrysler in Detroit and ask them if they'll help you out. Don't bother trying to reach Lee Iococca. He's too busy trotting around the bases after hitting that home run at his last time at bat. But maybe someone there wants you to buy another Chrysler some day, and will give you a new heater core and apologize for the tremendous inconvenience.