Send your comments or questions for Tom and Ray to: Car Talk Plaza, P.O. Box 3500 Harvard Square, Cambridge, MA 02238. Listen to them Saturdays at 10 a.m. on 91.3 FM or 88.5 FM. Visit them on the Internet at www.cartalk.com.
Dear Tom and Ray:
I have a 2002 Nissan Altima that for the past six months has been losing oil at the rate of about a quart per month.
I thought that it might be either leaking oil or burning oil. However, there are no drips under the car, and it recently passed emissions testing during inspection (I would have thought it would have failed if it was burning oil).
Anyhow, I’m perplexed. What’s happening to the oil? Otherwise the car runs fine, and the gas mileage is as it always has been.
When the oil starts to get low, I notice a slight metallic fluttering sound in the engine. When I top off the oil, that goes away.
Is this a sign of serious engine problems? Thanks! — Mike
RAY: For some people, losing a quart of oil a month is a serious engine problem. For my brother, losing a quart every 10 minutes is but a minor inconvenience.
TOM: You’re burning the oil, Mike. If it’s not leaking, you’re burning it. Burning oil won’t necessarily cause you to fail an emissions test.
Most emissions testers measure carbon monoxide, carbon dioxide and unburned gasoline. There’s no “engine turning to crap” oil-burning detector in the emissions tests yet.
RAY: And that’s a lucky thing for you! Either your rings are shot (big, big money), or you have worn valve guide seals (medium money).
TOM: The “metallic fluttering” sound you’re hearing is your engine suffering from oil deprivation.
My guess is, it’s either the lifters collapsing, or it’s the timing-chain tensioner letting the chain slap against its cover — neither of which is good.
RAY: So you have two choices, Mike: You can have your mechanic start taking apart the engine (and pray for bad valve guide seals), or you can keep a close eye on your oil level, and just keep driving.
TOM: That’s the option we thought you’d pick! If you decide to just keep driving it, from now on you have to learn to add the oil BEFORE you hear those noises.
RAY: So Step 1 is to check the oil more often. Once a week is good, for now. And check it in the morning, before you start the car. That way, you don’t even have to wipe off the dipstick. You just pull it out, have a look and go.
TOM: Step 2: Start adding oil when you’re half a quart low. That should keep those key parts from being deprived of the oil they need to work correctly.
RAY: Finally, keep changing the oil regularly. A lot of people make the mistake of thinking that adding oil is a substitute for changing oil, but it’s not. In fact, when your engine is regularly running low on oil, the remaining oil is working even harder. Three quarts are doing the work of four. So that oil needs to be drained out and replaced more often rather than less often.
TOM: The oil burning will eventually get worse, Mike. At some point, it’ll become unsustainable — unless you move to Saudi Arabia and drill your own backyard well. But if you’re careful, you probably can keep this car going for a good long time. Best of luck.
Embarrassing car is just the thing for a teen
Dear Tom and Ray:
About a year and a half ago, my dad bought a white ’92 Volvo station wagon off Craigslist for $500. I’m turning 16 next spring, and he expects it to be my car.
He thinks it’s fantastic because it was so cheap, but the car is older than I am, and it’s a piece of junk.
We went over a speed bump once, and the fan for the air conditioner fell out of the bottom. And I hate to be picky, but it’s pretty embarrassing to ride in.
I was hoping that you might have a good excuse as to why I shouldn’t have to drive it, because my dad loves your show.
Thanks so much. — Emily
TOM: Gee, Emily, I feel terrible about this. Just awful!
RAY: Yeah. Unfortunately, this is exactly the type of car we recommend that parents buy for their teenagers. Your father probably got the idea from hearing us talk about it. It’s safe, it’s slow and it’s ugly — the perfect car for a teen!
TOM: Right. It’s ugly and embarrassing, so you won’t drive it unless you have to. Parts are falling off of it, so you won’t be tempted to stray far from home. And it’s a tank, so if you do make a mistake (which many teenagers do), you’ll have a better chance of surviving it.
RAY: So I’m afraid we’re not going to be much help here, Emily.
TOM: Wait. I’ve got it. Emily, next time you’re in the car with your dad, look toward the back and say, “Those back seats fold down, right, Dad?” And when your dad says: “Sure they do. Why?” You say, “Well, with the seats folded down, I bet there’s plenty of room for two people to lie down back there.”
He’ll have you in a ’92 Volvo SEDAN by Monday, Emily!
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