Tip & How-To about 1987 BMW 5 Series

Bad O2 sensor

If your car has lost several miles per gallon of fuel economy and the usual tune up steps do not improve it. This *is not* a pointer to O2 failure, it just brings up the possibility. Vacuum leaks and ignition problems are common fuel economy destroyers. As mentioned by others, the on board computer may also set one of several failure "codes". If the computer has issued a code pertaining to the O2 sensor, the sensor and it's wiring should be tested. Usually when the sensor is bad, the engine will show some loss of power, and will not seem to respond quickly

Posted by on

Cars & Trucks Logo

Related Topics:

Related Questions:

3 Answers

what are the causes of high fuel consumption in fx35 infinity


need tune up , heavy foot . road conditions--mountian terrain,,city stop and go

Jul 16, 2016 | 2005 Infiniti FX

4 Answers

how many miles do u get for a full tank of gas on a v8


It just depends on your tank size. You probably get about 15 -18 miles per gallon. 13 gallon tank would be around 200 miles. 15 gallon tank around 232 miles.

Mar 06, 2011 | 1997 Cadillac Eldorado

2 Answers

how do I improve my fuel economy in my 1997 Hyundai Sonata GLS?


Here are some tips on how to improve your fuel economy:
- Going fast is so tempting. Not only do we do it to keep up with the flow of traffic, but if we can save even five minutes, it seems worth it. But if you're on the highway, driving 60 miles per hour instead of 70 mph will save you 2-4 miles per gallon over the duration of your trip.
- Take it easy on the throttle. Don't accelerate quickly or stomp on the brakes. Coast to a stop. You'll save on fuel as well as wear and tear on your brakes, which will save you even more money.
- Shut down. If you're waiting somewhere for a while, like at a train crossing for instance, turn off your engine. Even if it's just for a minute, it can make a difference in your fuel economy, especially if you drive in the city a lot.
- Don't warm up your vehicle for more than 30 seconds. This is a tough one, especially for us here at Consumer GuideĀ®, where Chicago's frigid winters are a way of life. Thanks to technology, however, most modern fuel-injected cars only really need 30 seconds to warm, and hot air can start blasting into the cabin very shortly thereafter.
- Windows up. Again, this is tough, especially on pleasant days. But having the windows down creates aerodynamic drag that causes an engine to work harder. On the highway, this can decrease fuel economy by up to 10 percent.
- Check your tire pressure. Making sure your vehicle's tires are set to the recommended pressure can increase fuel economy by as much as 3.3 percent.
- Breathe easy. Next time you get your oil changed, have the air filter checked as well. Replacing a dirty air filter with a clean one can save up to 10 percent on fuel costs.
- Make sure your vehicle is in top running order. Read your owner's manual and follow the manufacturer's recommended maintenance schedule. If it's time for a tune up, do it and you can realize up to a 4.1 percent increase in fuel economy.
- Buy the right gas. Your owner's manual will list the correct octane gasoline you should use for your vehicle. Purchase whatever is recommended and no more. Premium-grade fuel is more costly and won't improve economy in vehicles designed to run on regular.
- Lighten up. The less weight in your vehicle, the better your fuel economy. Clean out that trunk!
- Grease up. Using the manufacturer's specified motor oil, and changing it per factory recommendations, can improve fuel economy as well.
- Combine trips. Don't run out two or three times a day. Hit all the stores you need to visit at once, and if possible, go to shopping malls where you can park and walk to several stores at the same time.
- Cool down. Gas up on cool mornings. Fuel is denser when cold. Gas pumps measure by volume, so if you pump when it's cold, you get more gas for your buck.

Dec 12, 2010 | 1997 Hyundai Sonata

2 Answers

had a poor gas milage only 23 mile per gallon city


Keep your services up also on the transmission. Try this simple fix, get some octane booster and injector cleaner and put them into the tanks $8. Hopefully this will help break off the carbon deposits in the injectors and give you a smooth economical ride. Good luck

Nov 20, 2009 | 2009 Hyundai Accent

1 Answer

lost gas mileage please


Lost gas mileage. I would have to assume that you are not getting the require mile per gallon. For example If the car book say 32 miles per gallon. You are getting about 20 to 25 miles per gallon.
If you want to improve the your gas mileage then you have to do the required maintenance
Oil change every 3000 mile
tune up as required
Air filter
If the wiring spark plug wire is old and crack then it need to be replace.
If you park out side and the batteries is about 5 years old have it check
If you buy the car new, you will have a car book follow the maintenance routine.
If you have done all the maintenance and the gas mileage is low than recommended then take it to a shop to figure out if some thing is wrong or not preforming as it should.
I do hope this help you.

Mar 01, 2009 | 1999 Chevrolet Malibu

Not finding what you are looking for?

1,677 people viewed this tip

Ask a Question

Usually answered in minutes!

Top BMW Experts

Frankie B

Level 2 Expert

65 Answers

Fred Sops

Level 2 Expert

272 Answers

Doberman

Level 2 Expert

254 Answers

Are you a BMW Expert? Answer questions, earn points and help others

Answer questions

Loading...