Piston Slap: A Rather Thirsty Escort?

Sajeev Mehta
by Sajeev Mehta

TTAC Commentator Weltron writes:

Hi Sajeev!

The car I am writing about today is my winter beater, which is a 1999 Ford Escort SE sedan which says it has a tick over 155,000 miles. The problem I’m having with it is it it getting dreadful gas mileage. My average tank is about 19 miles to the gallon (in comparison that is what my twin turbo straight six Volvo gets around town). Over the winter I replaced both of the o2 sensors and got a marginal improvement (about .4 mpg).

And here’s the kicker: the dumb thing runs perfectly. No error codes or anything. Idles smooth and everything (well as far as Escort refinement goes). When I go on the highway (which is fairly often) I can see upward of 21… If I’m lucky.

Help please! I’m debating on whether to sell it or not due to this gas mileage problem for something bigger (thinking an Oldsmobile Eighty Eight/LSS or if I’m feeling lucky … an Aurora if I do end up replacing the Escort.) Thank you in advance for your help.

P.S. Here’s a list of what has been replaced/cleaned since the fall.

Mass air flow sensor cleaned


New air filter


New spark plugs/ plug wires


New o2 sensors (both upstream and downstream)


New muffler


New tires

Sajeev answers:

It’s funny how well-maintained vehicles occasionally have an obvious problem that’s impossible to diagnose. But going to the beautiful, enjoyable yet expensive and complicated Northstar powered Oldsmobile is the wrong move!

You’ve done the basics, kudos to you. That makes our job easier. Considering your Volvo drives in the same manner (presumably) there’s certainly a minor problem outside of driver error. And I wouldn’t be so adamant if it didn’t happen to me:

Try changing the fuel filter first, then get new/reconditioned fuel injectors.

That’s it. I know you’ve slooooowly been losing power and efficiency. Perhaps you notice a mysterious fuel smell? The injectors are no longer turning on/shutting off correctly. And when you get ’em installed, ZOMG SON, note the instant acceleration improvement and the later MPG lift.

So go ahead and keep it, even if the cylinder head might be a problem in the future.

[Image: Shutterstock user Chill Chillz]

Send your queries to sajeev@thetruthaboutcars.com. Spare no details and ask for a speedy resolution if you’re in a hurry…but be realistic, and use your make/model specific forums instead of TTAC for more timely advice.

Sajeev Mehta
Sajeev Mehta

More by Sajeev Mehta

Comments
Join the conversation
2 of 86 comments
  • Beerboy12 Beerboy12 on Jul 28, 2014

    I would have suspected a fuel leak in the return lines. Cold weather plus a short commute would definitely return bad MPG to. A faulty thermostat that does not block water from the motor in the warm up faze could add to the problem to. Basically the engine block and oil never get to running temp. so the car is running on it's electronic little "choke" all the time.

  • Chicagoland Chicagoland on Jul 29, 2014

    I had 2000 Scort for a beater and had the thermostat replaced, and that helped mileage. But I also agree with fuel filter and injectors. It's 15 years old, so age wears a motor out also.

  • Varezhka The biggest underlying issue of Mitsubishi Motors was that for most of its history the commercial vehicles division was where all the profit was being made, subsidizing the passenger vehicle division losses. Just like Isuzu.And because it was a runt of a giant conglomerate who mainly operated B2G and B2B, it never got the attention it needed to really succeed. So when Daimler came in early 2000s and took away the money making Mitsubishi-Fuso commercial division, it was screwed.Right now it's living off of its legacy user base in SE Asia, while its new parent Nissan is sucking away at its remaining engineering expertise in EV and kei cars. I'd love to see the upcoming US market Delica, so crossing fingers they will last that long.
  • ToolGuy A deep-dive of the TTAC Podcast Archives gleans some valuable insight here.
  • Tassos I heard the same clueless, bigoted BULLSHEET about the Chinese brands, 40 years ago about the Japanese Brands, and more recently about the Koreans.If the Japanese and the Koreans have succeeded in the US market, at the expense of losers such as Fiat, Alfa, Peugeot, and the Domestics,there is ZERO DOUBT in my mind, that if the Chinese want to succeed here, THEY WILL. No matter what one or two bigots do about it.PS try to distinguish between the hard working CHINESE PEOPLE and their GOVERNMENT once in your miserable lives.
  • 28-Cars-Later I guess Santa showed up with bales of cash for Mitsu this past Christmas.
  • Lou_BC I was looking at an extended warranty for my truck. The F&I guy was trying to sell me on the idea by telling me how his wife's Cadillac had 2 infotainment failures costing $4,600 dollars each and how it was very common in all of their products. These idiots can't build a reliable vehicle and they want me to trust them with the vehicle "taking over" for me.
Next