Help only geting 9-10 mpg

[Adam Hartman]

Any suggestions on what may be wrong i'm only getting 9-10 mpg city driving. I have an 01 4x4 4.0L auto trans there is no check engine light on I have no extras its bone stock. javascript:insertAtCursor(document.forms['MESSAGEFORM'].MESSAGE,':cheeky:')

 

[Phil Frady]

Dont race red light to red light, gradual starts and stops. In the city you should be at least 14mpg.

 

[scott degroot]

DIrty MAF

 

[Robert Caffyn]

Did you put on oversized tires and not correct the speedo?

 

[John G]

Oxygen sensor?



I'm guessing that your parking brake isn't engaged, or you would smell it.

 

[Jerry Gerner 2]

I agree with the first two, drive it like a grandma or atleast more sensible and it'll help out alot. I've dialed it down on the speeding and especially the fast takeover and it's helped out dramatically. Also if you haven't tuned up your Trac it's well overdue. Clean the IAC, MAF, new air filter, fuel filter, plugs, wires, seafoam the intake, etc... All of these will help you improve your mpg's and bring some life back into your Trac. Next time you work on your brakes make sure to take the caliper slider pins apart, clean them and regrease them, this may not seem like it would hurt mpg's but the way the brake pads sit against the rotors if their not greased then they won't slide bake away from the rotors creating more drag. Get the trans flushed and new filter if still original along with the transfer case and both rearends if you have 4wd. You don't have to rush out and do all these things but it'll help greatly. Look in the projects section, theirs very detailed how-to guides to help you do these things yourself and save a ton of money even if you're not mechanically inclined. Hope this helps. nline::banana:

 

[Richard L]

The cheapest things are to insure your tires are inflated properly, and most people will recommend 4-5 PSI above what's on the tire inflation sticker. I used to keep my Sport Trac tires inflated to 34-35 PSI.



Also, don't carry a lot of excess weight in your truck...things like heavy tool boxes take more energy to get moving and driving in Stop-N-Go city traffic eats into your gas mileage because you must constantly keep accelerating and slowing down.



Watch you driving habits as bad driving habits can really eat into your gas mileage more than anything. Accelerate slowly, coast to the next stop light and brake slowly...if the light turns green before you have to come to a complete stop, it will take less gas to get you moving again.



Traffic is also a big factor and if you like to drive a little faster than the flow of traffic, you will spend more time slowing down and speeding up and that really eats up your mileage.



If you do all of the above and you still have poor mileage, you may want to start looking at some mechanical things on your truck. The MAF sensor and IAC can be cleaned by yourself and would be the first things I would look at.



Surprisingly the Air filter and fuel filter have little or no bearing on fuel mileage. They do effect high RPM performance and should be checked and replaced as needed, but they will not improve our mileage. Properly gapped spark plugs and good plug wires can give a slight fuel mileage improvement, but again, they effect performance at higher RPM's more than fuel mileage...especially not in low RPM city driving.



The concept of a tune-up to improve gas mileage is something that was true for old points and distributor ignition systems. When the points wore, they effected the timing of the engine which hurt performance and mileage, so points had to be adjusted every few thousand miles. Also the points contacts and the rotor tips would get pitted and reduce ignition voltage effecting mileage and performance.



Todays modern engines use all electronic ignition components, no distributor, no points, no ignition rotor etc., and the timing is controlled by the computer. If things get too far out of tolerance the computer will throw up a "Check Engine" light.



....Rich

 

[Todd Z]

Maintenance Maintenance Maintenance Maintenance



Fluids, Filters, plugs, Wires, PCV, Clean IAC, MAF and TB.....



and Driving habits



Todd Z

 

[Richard L]

I did not mean to imply that maintenance was not important nor should it be ignored. I only wanted to point out where to look first for fuel mileage improvements. Of course, if you have not changed the filters, or plugs, and wires since you bought the vehicle, you are probably not getting the best mileage the vehicle can provide.



It has been proven that air filters on newer vehicles keep the engine clean, but do little to improve gas mileage. Spark Plugs and wires only have a minimal effect on gas mileage so long as they are not misfiring which would/should trigger a CEL.



I am convinced that most poor gas mileage complaints are based on driving habits, and perhaps low tire pressure, and even inaccurate calculations, and less on the condition of the vehicle that appears to be running normally.



The IAC and MAF can effect mileage and may need to be cleaned...but unless there was a rapid, unexplained drop in mileage, I would assume driving habits or traffic conditions have changed and those are often the easiest and cheapest first steps to take to improve mileage.



Of course, this assumes that you have taken reasonable care of the vehicle and done the required mainenance.



...Rich

 

[JohnnyB]

Dont race red light to red light, gradual starts and stops. In the city you should be at least 14mpg.

That depends on what city you are talking about. I don't know about where the original poster lives but in NYC I never came close to 14 mpg in city driving. Actually in the 6 years or so that I had my '01 ST with the 4.0L I averaged 10.5 mpg overall. That's keeping track of every tank of gas.

 

[Johnny O]

Depends how much stop-and-go traffic you're in. All the time spent sitting still or at red lights averages in at 0 mpg.

 

[Richard L]

JohnnyO,

I certainly cannot argue with that. Most people do not seem to realize how much an extra long traffic light, or just catching an extra light or two on the way to work can eat into their gas mileage. Even the wind can impact fuel mileage and is often not taken into consideration.



That's why I think that a ScanGauge or the UltrGauge are such good tools for spotting where you are getting good mileage, and where you are loosing mileage.



I personally believe that driving habits contribute the most to your good a bad gas mileage, and the UltraGauge can help teach you driving techniques to improve your gas mileage. The next thing would be tire inflation since most vehicles on the road have tires that are dangerously underinflated.. The other causes you probably have very little control over like the weather, traffic, etc, and you just have to accept those.



...Rich

 

[user 62851]

I was at a point to only getting like 12-14 in my 04. I got my tires balanced along with right amount of psi. Grabbed an oil change and saw a little bit of improvement. Next I went to Ford, got them to change front/rear diff fluids, transfer case fluid and transmission fluid. Also I am running 89 fuel and I have increased to now get 18-20mpg. Next up is plugs. Oh yeah, I have 145k miles.

 

[Johnny O]

Even the wind can impact fuel mileage and is often not taken into consideration.

I used to have a Lincoln with an mpg thingy on the dash too and I would travel monthly across I-90 in NY to pick up my kids for weekends. It is very flat and the prevailing wind is west to east.

Once it was pretty windy all day and my mileage coming back was 6 mpg worse than it was on the way up.

 

[Adam Hartman]

I don't do hole shots off of stop lights. my driving habits are just fine I have replaced the MAF 6mo ago. The plugs are only a yr old Went for a road trip and only got 16mpg on highway somethings wrong maybe o2 sensors? tiers are inflated proper air filter is clean and i change my fuel filter every yr. I have not changed my trans fluid yet its still a bright red and not a burnt smell. Will be changing it soon just because I don't know when the last time its been changed. Really wish I had a scan tool to look at what the o2 senors are doing if there staying rich or switching back and forth like they should. I may replace them next just because im at 95000 mi and its close to time to change them.



If anyone has any other suggestions let me know much appreciated!

 

[Richard L]

adm,

If you have already done everything that was suggested here to insure your vehicle is in perfect running order, then the problem has to be in your driving habits, or traffic conditions in your area. Nothing to be ashamed of, nor am I criticizing you.



It does not take jackrabbit starts to kill your gas mileage in a Sport Trac. Any attempt to accelerate a heavy vehicle has a gas mileage penalty, and the faster you accelerate the more gas it takes. With something like an Ultra Gauge you can slowly pull away from a stop light and see that your mileage may drop to 4 or 6 MPG. The same applies to driving on a freeway with cruise control on. Everytime you encounter a slower vehicle and have to slow down you have lost momentum and it takes more gas just to get back that 5-10 MPH you lost. So even when you are on a freeway using your cruise control, traffic can still cause you to slow down and speed up and it's the speeding up that kills the gas mileage.



Of course we all know that when the traffic is heavier the traffic flow naturally slows down and speeds up in an accordian fashion.... To avoid that, I found that if I set my cruise to match or be slightly less than the vehicles in the slow (right lane) and find a nice opening, you can drive for very long distances without having to slow down and speed up because you rarely pass anyone....It requires some patience to drive slower, but it does work. It is not the driving speed that eats the gas, it's constant slow down and speed up cycles that sucks your tank dry.



...Rich

 

[H D]

I have an '01 4x4 with 32" tires, body lift and nearly all the same conditions you have mentioned. I don't go over 2k RPMs on most daily trips, and rarely get up to 2,500 RPMs on highway. I never exceed 2,500 RPMs. My gas mileage is closer to 17mpg than 10.

 

[Phil Frady]

I have replaced the MAF 6mo ago.

Why did you do that? Unless you were going for performance, those don't go bad. Also, since you changed the MAF, did you get one to match your injectors? No matter how large the MAF is, if you dont match the sample tube to the injectors, it doesn't help. You need to determine if it is for 19lb, 24lb, or 36lb injectors.

 

[Richard L]

Funmobile

Why did you do that? Unless you were going for performance, those don't go bad.

Where did you come to the conclusion that MAF's don't go bad??? They are a very reliable component, but they most certainly do go bad. I agree that if you go to many Ford dealers and they find the MAF is dirty (over oiling a K&N filter) etc, they will just replace it with a new one rather than trying to clean the old one...but that does not mean they never go bad.



Even if he did replace the MAF, he indicated that his truck is stock, so I would assume his new MAF is an OEM replacement MAF and he is running the stock injectors.



I think it's a bit of a leap to assume that he replaced the MAF with a performance unit, and that is the cause of his poor mileage.



90% of all gas mileage complaints are caused by simple things like tire pressures brand of gas used, and even more so by driving habits.



As an interesting side note:



Alcohol is a cheap way to increase octane but E85 fuel (85% alcohol, 15% gasoline) will result in about 20%-25% less fuel mileage...so the more alcohol in the fuel, the less gas mileage.



Now days most regular gasoline contains up to 10% alcohol. Since they cannot add more alcohol to increase the octane many brands use other additives and less alcohol to increase the octane in their premium gas blends. I don't know which brands use less alcohol in their premium blends, but I think this is probably why people claim to get better gas mileage with premium gas than regular.



During the gasoline crisis I have purchased some cheaper No-Name premium gas for my car and I can see a decline in my gas mileage compared to the better known brands like Exxon, Shell, or Chevron, so I suspect that some cheaper brands put more alcohol in their premium gas (not to exceed 10%) than the brand name gas stations.



Now the government is pushing the gasoline companies to increase the alcohol content of regular gas up to 15% which can damage your fuel systems if your vehicle is not E85 fuel compatible. Car manufacturers are already saying that if the alcohol content of gas goes up to 15%, they will void your new car warranty, and you will get even worse gas mileage !!



...Rich

 

[Johnny O]

Sometimes the problem is the gas itself too. Different parts of the country get different gas blends at different times of the year. Here we get the crappy oxygenated gas in the summer and while the 87 doesn't ping, I will get slightly better mpg running 89 instead of 87. Difference is $0.10 a gallon or $2.00 a tank and I probably save more than $2.00 per tank. A 3.0 Ranger I used to have wouldn't run for crap on the summer gas. The 4.0 in my last three trucks is more tolerant.