RAY: -- with us, Click and Clack, the Tappet Brothers and as promised, here's the answer to last week's puzzler, which you so...

TOM: Brilliantly, brilliantly.

RAY: As I described earlier. Here it is. A fellow comes into the shop the other day, and he complains that his Volvo, an older one is misbehaving. It seems to be losing power. It sputters. It has difficulty climbing hills, and he says it's especially bad if the tank is less than half full. Ah! We said Ah! Piece of cake. It's a classic problem of the intank fuel pump not working.

TOM: Yeah, of the two fuel pumps.

RAY: For years and years Volvo's have had an extra pump inside the tank, a feeder pump, which pushes fuel to the main fuel pump, which is located outside the tank. That main pump sends it to the rest of the way to the engine and eventually to the injectors, etc. etc. so when the intank pump fails, the car will still continue to run...

TOM: Because the other one is sucking it out.

RAY: The main pump is doing the lion share of the work, and it will suck the gasoline right through the broken intank pump and supply it to the injectors, but when the tank is low, it has difficulty doing this, and the pump will moan and groan and not supply enough pressure, etc.

TOM: Everyone who has taken freshman physics knows why that happens. Everyone, everyone!

RAY: Everyone.

TOM: Sure.

RAY: Who has taken freshman physics and...

TOM: Passed it! I left that out didn't I?

RAY: So anyway he says go ahead replace the pump for 900 bucks, see if I care. So we do it, and a week or two later he returns and says Jesus, thanks guys, the car runs great, but my mileage is down. You must have done something. They always says that. Why do you say that? You must have done something. It's off by at least ten percent. We say how could we have done anything.

TOM: We fixed it.

RAY: Right. We fixed your damn car, and now you're complaining that we've done something. I say well, ten percent is hard to measure so we throw him out and tell him he's dreaming. He comes back a few weeks later and says it's down even more. It's 15 percent now and getting worse; you did something wrong. Again we reassure him that we did nothing wrong.

TOM: Of course.

RAY: A head lock works wonders. He says I know it has something to do with that pump you put in the tank, so we go ahead and check the emissions and the timing and everything, and there is nothing wrong. We throw him out again.

TOM: Good. I like this customer is always right policy.

RAY: We've come to realize -- when he returns for the third time with his brother-in-law Bruno, that he's right. Even though we did nothing wrong, I add we did nothing wrong putting in the new pump.

TOM: You were remiss.

RAY: We did, by putting in the new pump, make his mileage drop. We missed something. We missed something. What we missed is that there is a piece of tubing that goes between the tank pump and the main pump, and it had a little pinhole in it.

TOM: So the little pump inside the gas tank pumps fuel along this tube into the main pump. The main pump then pushes it the rest of the way to the engine.

RAY: Now with the intank pump broken, this little pinhole did not cause gasoline to leak out because there was suction created in that tube. When we replaced the feeder pump, we created positive pressure in that line between the two pumps. Even though most of it was being sent to the injectors, just enough was leaking out through this little pinhole to cause this 12-point 7.5 percent drop in mileage. So he was right even though we didn't do anything wrong.

TOM: I mean that's an interesting...what if that were a -- this brings up an issue, a legal issue. What if this were a life threatening thing.

RAY: What if his car had burst...

TOM: What if it burst into flames and he died? Then he wouldn't be able to see. Well, what if he didn't quite die, unfortunately.

RAY: Burned beyond recognition?

TOM: Burned beyond recognition.

RAY: But his memory was in tact, and he could call his lawyer.

TOM: He still had enough energy left to call his lawyer, right. The thing is are you required then to look to see that there are no little pinholes, which could never, ever happen except once in a while because you would install the pump, you get in the car, you turn the car, the thing would run like a dream, and you'd say it's running like a dream, everything is fine.

RAY: Yeah, we never saw the pinhole because it was pointing up and spraying gasoline on the under side of his car.

TOM: Sure, and you wouldn't even see it.

RAY: Right near that hot exhaust system.

TOM: You wouldn't see it. Interesting.

RAY: Interesting.

TOM: Yeah.

RAY: Yeah, whose responsibility is it? Ours.

TOM: It is.

RAY: It is, unfortunately.

TOM: I don't think so.

RAY: Well, the judge thought so. Anyway, who's our winner?

TOM: The winner is James Nofi, N-o-f-i, from Flushing, New York and for having your correct answer chosen at random James Nofi from Flushing, New York from all the right answers that we got this week, you, James Nofi, will get one of our tenth anniversary Car Talk t-shirts with our current slogan, "Celebrating Ten Years of Bad Car Advice.

[ Car Talk Puzzler ]