Q: My 88-year-old mother has a 2005 Buick LaCrosse with 15,000 miles on it. It only gets driven to the grocery store, hair salon and church. But that has been the case for all six years she's owned it. Now, in the past three months, three new batteries have gone stone-cold dead after four to six weeks! The Buick service department says the problem is "She doesn't drive it enough!" Heck! For nearly six years, she "didn't drive it enough," and it used the same battery! I can't get them to tell me why it apparently is sucking the life out of the batteries now. Any ideas? Gary
Ray: Well, I agree with you, Gary. If the problem were that she didn't drive it enough, why did she have no problem with the battery for the first six years?
Tom: There are two possibilities. One is that something inside the car is draining the batteries. It could be a faulty alarm system, dome light or some other electric accessory.
Ray: The dealer should be able to figure that out by putting an ammeter on the car when it's shut off and seeing if there's a current drain.
Tom: But I think the more likely problem is that her charging system isn't working.
Ray: Here's the scenario: She drives the car a few times a week. Normally, that's enough to recharge the battery. But at some point, the alternator starts to underperform.
Tom: Without the battery recharging properly, in the course of a few weeks or a month, the battery runs down and dies. So she takes it in. They don't test the system rigorously enough and just sell her a new battery.
Ray: At first, everything seems fine, but the new battery isn't being sufficiently recharged either. So it lasts for a month or so, and then it dies. This process is repeated three times, until you realize that the guys at this particular service department are complete knuckle-scrapers and you go somewhere else.
Tom: Where, hopefully, they do a thorough test of the charging system, figure out what's wrong with it and replace the alternator or whatever else needs to be replaced.
Ray: And if you end up needing another new battery, it's reasonable for you to go back to the original dealership, explain to them that they missed the problem with the charging system and ask them to reimburse you for the battery or three they sold you.
Feeling the heat
Q: I had a heater core on a 1999 Dodge Dakota Sport replaced, and I now have heat all the time without it being turned on. I was told that I was feeling heat from the engine because there is no insulation on the firewall. I didn't have this problem before the new core was installed. What, if anything, did they forget to do? Greg
Ray: That's not heat from the engine bleeding through, Greg. That's heat from the heater. And it's likely the fault of the guys who changed the heater core.
Tom: But before we conclude that they're absolutely to blame (we'll get to that soon enough), let's look at one other possibility. The heater controls in this truck are operated by engine vacuum. There's a check valve under the hood that helps the system maintain vacuum during hard acceleration.
Ray: Right. So if that check valve were broken, your blend doors (the flaps behind the dashboard that regulate how much heat comes into the cabin) can pop open during hard acceleration.
Tom: So if you're getting a surge of heat only when you're accelerating hard or climbing a hill, then this five-dollar check valve could be the problem.
Ray: But if you're getting heat all the time - which is what you say in your letter - then these guys screwed something up. Maybe they jammed a blend door so it can't close all the way. Or maybe they forgot to reattach a vacuum hose.
Tom: The reason they're trying to get rid of you is because rescuing the Chilean miners was easier than getting to the heater core in this vehicle. They don't want to do it again. For free. So they're hoping you'll just go away, or start driving around in your bathing suit.
Ray: So you're just going to have to be a little more insistent when you go back to see them, Greg. Bring a couple of large friends with you. Or a lacrosse team.
Tom: They don't want to take out the dashboard again, but that's what happens when you screw something up - you have to do it again until you get it right.
King Features Syndicate