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Back on the Coast

Back on the Coast

Monday, March 3, 2008

Fuel Economy Part One: Vehicle Maintenence

Fuel economy is a big issue these days. Everyone is feeling the 'pinch' at the gas pump. Governments keep assessing new and higher taxes to automotive fuels; the oil industry seems to always have a reason to increase the price. To top it off, we as vandwellers, operate vehicles that don't have the best miles per gallon (MPG) rating. So, I'm writing this series of articles to help us all get the best gas mileage possible. If anyone has any suggestions I haven't covered, please email me and I will revise these articles.

In this article I'm just going to cover how vehicle maintenance effects fuel economy. Not only does keeping your vehicle properly maintained give you the best performance and safety, it also fetches more MPG. Many vehicle owners quite often reason, "If it ain't broke, don't fix it." Well, with today's rising fuel cost, that old idea doesn't work anymore. Consider getting manuals for your vehicle for maintenance schedules; at least consult your owner's manuals.

Some maintenance routines listed here are easy and economical to do. Some require more money and probably a mechanic to perform. But, sooner or later, depending on how high mileage and/or how long you keep your vehicle, you may have to do them all. By not keeping your vehicle running properly, you are costing yourself money at the pump and you are polluting the air needlessly. You are going to pay one way or the other; only you can choose what is right.

1/Check and replace your air filter regularly - Replacing a clogged air filter can improve your gas mileage by as much as 10%. Your manual maintenance schedule (MS) will probably say to replace/inspect every 10,000 miles or so; but if you live in a dusty, dirty area, it may get clogged sooner.

2/Replace your fuel filter - A clogged fuel filter can choke the flow of fuel to your engine, causing it to run rough. You can't inspect it, you just got to replace it according to the MS. If you live in an area where you suspect the fuel could be suspect, replace it more often.

3/Renew your engine oil and filter - Refresh your engine oil according to your vehicle MS and always replace your filter when you do it. You can improve your gas mileage by 1 - 2 percent by using the manufacturer's recommended grade. For example, using 10W-30 engine oil in an engine designed for 5W-30 can lower your gas mileage by 1-2 percent. Also, using your oil for too long and allowing it to get real dirty will do the same thing; so stick to the MS and freshen your engine oil regularly. Consider using synthetic oil; it is more slippery, which reduces friction and helps your engine's efficiency.

4/ Clean your fuel injectors - When you change your oil, consider using a fuel additive which cleans your fuel system and maybe once between. This helps reduce carbon deposits on your injectors which hamper them from working properly.

5/ Consider your oxygen sensor - For fuel injected vehicles, the oxygen sensor which controls your fuel/air mixture is key. If you have a higher mileage vehicle or a vehicle that was very poorly maintained, your sensor may be dirty or malfunctioning. Check it out, and see if it needs maintenance. An oxygen sensor that is malfunctioning can cause a loss in fuel economy of up to 40%!

6/ Maintain/Replace your sparks plugs and wires, distributor cap and rotor - This is basic ignition maintenance. Refer to the manual MS for inspection and replacement. You need a good spark to 'fire' the fuel properly in your engine.

7/ Inspect and maintain your brake system - Brake systems that are out of adjustment and needlessly dragging will reduce your fuel economy.

8/ Wheel Bearings - In higher mileage vehicles, this is something many people overlook; I guess it's that 'out of sight, out of mind' mentality. But if your bearings aren't lubed or adjusted properly according to your vehicle MS, they can effect the efficiency and safety of your van.

9/ Tire inflation and alignment - You can improve your gas mileage by keeping your tires inflated to the proper pressure. Under-inflated tires can lower gas mileage by 0.4% for every 1 psi drop in pressure for all four tires. Properly inflated tires are safer, maximize your traction on the road and minimize tire tread wear.

10/ Exhaust system considerations - If your vehicle has high mileage or was poorly maintained, your exhaust system may need some overhauling. Catalytic converters can become plugged with old age, which will restrict your exhaust flow and cause your engine not to perform properly. Also, your original exhaust system is designed to operate with your engine within specific performance perimeters; try to replace components with similar products and sizes.

The basics of vehicle maintenance are paramount to fuel economy; other important factors are gas and vehicle purchasing and driving technique. While each separate area may not affect your MPG much, if several areas are out of specification, it can really add up. You can save a lot of money by doing the work yourself; but, buy good tools, learn how to do the job properly and practise safety. Because I've been working on my own cars for 30+ years, I perform about 90% of the above work myself; the other 10% I take to a shop because I don't have a lift, or the tools, or it's too cold outside. Sometimes it's just not worthwhile to do it yourself; you gotta' make that call. Always be careful when working on your van. If you don't feel confident, don't do it! Take an auto shop course, or at least work with knowledgeable people.

Next MPG article: Gas Purchasing


Anonymous said...

There are some aftermarket air filters (K&N, I think) that claim to increase gas mileage by 2-3 mpg, and the few folks I've known who've tried them confirm this. They're not cheap at over $100, but are permanent, cleanable filters and will pay for themselves with the savings.

You can't overemphasize the role of tire pressure in economical operation. It's often overlooked and neglected, but the easiest thing in the world is to buy a tire guage for every vehicle you own, keep it in the glove box, and check your tires at least once a month. In addition to better fuel economy, you will almost certainly prevent a roadside wrestling match with a flat tire ... on a freeway, at night, in the rain, etc.

Thanks for the tips.

Best wishes,


The Urbanvandweller said...

Hi, Rick - I've used a K&N filter on a previously owned vehicle. While it definitely aspirated the engine better, creating slightly more 'pep', I didn't realize any noticeable MPG gains (<.5 miles per gallon). I keep track of my gas mileage on a regular basis, and average any gains or losses over at least 4-5 tankfuls. I've never heard of anyone getting this kind of increase (2-3 MPG) with these filters. What kind of vehicles are they, I'm curious; I'm happy for those owners!

Cheers, Urban Vandweller