Piston Slap: At Liberty To Discuss Fuel Economy?

TTAC Commentator Libertyman03 writes:

Hi, just wanted to say that this is one of my favorite posts on TTAC. I look for Piston Slaps everyday. And since I value the advice, and the comments from the others, I decided to write in with my question: I have a Jeep Liberty (hence my username), and I like it a lot. But it uses SO MUCH GAS.

I have tried changing my driving style, change the oil regularly, change air filters and what not, and still it sucks down gas. It’s an ’03 with 82,000 miles, so it still has lots of life, but I can’t help but think getting rid of it for something more fuel efficient would be a good idea.My question then; what else could I do to stretch the Jeep’s fuel mileage?

Or should I just trade the Jeep on something smaller and more fuel efficient? My parent’s are leaning toward the latter, but I like the 4WD of the Jeep (I live in Pennsylvania, and winters can be pretty bad). If I get a new car, what should I get? I want something pre-owned, preferable 4 or 5 doors, and manual. I would also like to keep it under $8000.

Sajeev answers:

Finding a fuel efficient Jeep Liberty (sans Diesel) is like meeting an honest and transparent PR Flack. So think about this: the more efficiently you drive in the city, the closer you get to the vehicle’s EPA highway mileage rating. If that top figure isn’t acceptable, you got the wrong ride.

But still, addressing mechanical wear or unnecessary body add-ons is mandatory to see some sort of improvement. For example: fixing under inflated tires, removing off-road tires and body ornamentation is a good start. If you have the Liberty’s roof rack or light bar installed, sell them!

Then again, penny-wise and pound-foolish: with an $8000 budget, you’re selling a perfectly good Jeep for somebody’s problems masked behind the sheetmetal of something more efficient. But is it cost efficient? One unplanned trip to the mechanic on your “new” car negates any fuel savings for months. It’s not worth the risk. Who cares if you bought the wrong vehicle? Stick with the enemy you know.

Bonus! A Piston Slap Nugget of Wisdom:

Since all vehicles pass EPA noise pollution guidelines, installing a high flow, cold-air intake actually helps your vehicle’s mileage. Slightly. Very, very slightly.

The logic goes like this: deleting the factory’s intake resonators and necked-down tubing results in less effort at throttle tip-in. And if that decreased effort to reaches the same cruising speed, you burn less gas than before. But the good aftermarket intakes aren’t cheap: and $250 buys plenty of fuel.

The smarter move is to replicate their work via Home Depot plumbing section, capping off resonators and replacing small diameter tube, DIY style. While you might save enough fuel to justify the effort years (yes, really) from now, you’ll enjoy better throttle response and a “cooler” engine note. And you’ll do something entertaining in your spare time: it sure as hell makes me feel better about all the gas I’m burning!

(Send your queries to mehta@ttac.com)