I own a 2010 Accord EX-L, four-cylinder. I like the car a lot. Its mileage is a bit disappointing, however, especially in city driving. The EPA ratings for the 2010 are 21 city/31 highway/25 overall. I’ve noticed that the exact same car for 2011 is advertised at 24 city and 34 highway. I asked my dealer about this and he didn’t know why.

QUESTION: I own a 2010 Accord EX-L, four-cylinder. I like the car a lot. Its mileage is a bit disappointing, however, especially in city driving. The EPA ratings for the 2010 are 21 city/31 highway/25 overall. I’ve noticed that the exact same car for 2011 is advertised at 24 city and 34 highway. I asked my dealer about this and he didn’t know why. He said it uses the same engine and transmission as the 2010. Honda customer assistance hadn’t a clue. Any ideas why? Was onboard computer reprogrammed, perhaps to change the shift points? If so, would this degrade performance? Could the 2010’s computer be reprogrammed to achieve this? Thanks.


ANSWER: Each new model year, vehicle electronics are recalibrated and updated, the same holds true for personal computers and cellphones, etc. The cars may use the same engine transmission trim and interior etc., however, the computer programming, even fuel injectors and camshaft timing and profile, can all be different. The answer to your question is, the computer cannot be altered by the dealer. All vehicles, both gas and diesel, have to be certified for emissions before they can be sold in the U.S. There are some aftermarket companies that sell computer reprogrammers to increase power and fuel mileage. The question is do these aftermarket programmers work? The answer is only in some applications under some conditions. Would I spend the money for a reprogrammer? The answer for a four-cylinder is no. The best way to increase gas mileage is keep the tires inflated to the proper pressure, clean air filter, no extra junk in the trunk and full synthetic oil. Driving habits also play a big role in fuel mileage.


 


QUESTION: My issue is with the oil pressure gauge in my 1993 Lincoln Continental. The gauge falls below normal and the bell rings incessantly. The light flashes, showing low oil pressure. That continues for a while, and it comes right back up to normal. There are times it doesn’t drop at all. It could do this up to a day, and then the problem returns. Daily checking of the oil level is normal and clean; we have it changed before every 3,000 miles. We’ve changed all sensors and the oil sensor twice. We also had the electrical system checked on the computer, and the results were normal. We would like your advice on what you think is causing this and how we can correct it.


ANSWER: I received a lot of these questions in the last month or so. The first step is to actually check the actual oil pressure with a mechanical oil pressure gauge. With the gauge connected, start the engine, since oil pressure will be higher when the engine is cold. As the engine warms up, it’s normal for the oil pressure to drop. If the oil pressure is 15-20 pounds at hot idle in gear, this is normal. When the engine speed is raised, the oil pressure will also rise. If the engine is older such as yours and has 90,000 miles plus, the use of high mileage oil, with a higher viscosity such as 15w-40, can raise the oil pressure enough to keep the bells from ringing. High performance oils also can be a solution to low oil pressure at a hot idle. This is the last step after the engine has been checked by a technician.


 


QUESTION: We own a 2004 BMW model 325CI two-door. For the past three years we have detected a strong oil odor in the interior cab and trunk. Oddly, BMW service said they do not detect any odor, which I can’t believe. Other lay people have confirmed the strong odor when they are in the car. Recently, the check engine light went on and I had it serviced by a company other than BMW. The technician found fault code P0174 and noted, upon further testing, the engine had excessive crank case ventilation. He replaced the crank case vent valve, vent pipe, connection line, return pipe and engine air filter. Engine light was reset. The oil smell is still present. Any suggestions? Thanks.


ANSWER: For an oil smell to be smelled in the interior of any vehicle, the smell has to start under the hood or exhaust. The fault code p0174 is a lean condition due to much unmetered air entering the engine. I would take the car to an independent shop and have them check for oil leaks under the car. There is no way to actually know the problem without looking at the car.


 


QUESTION: I recently purchased a 1993 Oldsmobile Cutlass Ciera-S six-cylinder with 3,500 miles. The car was driven for about a year when purchased new, then garaged until I bought it. The car was thoroughly checked and is mechanically sound except for a nonworking fuel gauge. I use the trip odometer to monitor fuel level. The car has a 15-gallon fuel tank. When I get down to four to five gallons of gas in the tank, the car will stall upon a sudden stop or sharp turn. It also has a significant power loss when I have the a/c on, but only when below half a tank. When the tank is full the car runs great. Hope you can help, it’s a little difficult keeping the tank full all the time.


ANSWER: It sounds like the fuel pump pickup is sucking some air, not gas. The computer also gets information from the fuel level sender in the gas tank. On some vehicles, when the fuel level is below one-fourth, the computer will richen up the fuel mixture. Continued driving running the gas low can contaminate fuel injectors from debris sucked up from the low fuel level. I suggest replacing the fuel module and fuel filter.


 


Junior Damato writes weekly about cars. You can send questions to him care of the Old Colony Memorial, 182 Standish Ave., Plymouth, MA 02360.