For those who want to improve their fuel economy, or are wondering why it's not as good as it ought to be...

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3
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0answers
32 views

Loss of engine power between 2100 and 2500 RPM on humid days - 2011 Malibu

I drive a 2011 Chevy Malibu LT (4 cyl, 2.4L, 6 spd. automatic) and have been experiencing this problem for the past year and a half. Basically, whenver its hot (90f+) and humid out, my car exhibits ...
3
votes
0answers
50 views

Calculating MPG from MAP sensor (or converting MAP data to MAF data)

My 2002 Honda Accord V6 has a Manifold Absolute Pressure sensor (MAP). I understand that this sensor gives out information in pressure units (psi or equivalent). After doing a bit of research, I ...
7
votes
5answers
788 views

Is shifting to neutral on a decline more fuel efficient than keeping the gear engaged?

I always had the habit of shifting to neutral on long declines and using the brakes to slow down as needed. Intuition made me believe I'd be saving fuel as opposed to keeping a gear engaged. However, ...
2
votes
1answer
65 views

What is Total litres (reserve, usable)15 litres (3.2 litres reserve, 2 litres usable)?

I bought a new bike(Pulsar 150), and while reading its specs in the user manual i found Total litres (reserve, usable) = 15 litres (3.2 litres reserve, 2 litres usable). what does this mean, I assume ...
5
votes
1answer
52 views

Oily Sludge in the Intake Manifold

When taking off the throttle body to clean my IAC, I noticed that there was a thick layer of oily sludge coating pretty much everything inside the intake manifold: I have two queastions: How did ...
1
vote
1answer
59 views

fuel consumption

What is the normal fuel consumption for injection type Toyota carina e 1.6 cc 4A engine? My 1995 Toyota Carina e car gives 9.5km/l in city and 12 km/l on highways. How can I increase it more? toyota ...
11
votes
1answer
224 views

How much does spark plug gap affect fuel efficiency?

I've read conflicting reports regarding how plug gap can affect fuel efficiency. For example, I've read that too small a gap won't cause a clean burn, or that too large a gap can cause misfires due ...
4
votes
1answer
32 views

How is “Fuel consumption (economy) - combined” Calculated?

I have a Mazda - 323 S V (BA) - 1.8 i 16V (114 Hp) and the data sheet for it says: Fuel consumption (economy) - combined 7.9 l/100 km. How is this calculated and under what driving conditions?
5
votes
1answer
274 views

How does ambient temperature affect engine efficiency and fuel consumption?

I remember from my physics class that the ideal-gas Carnot engine is more efficient if the temperature difference between the heat source and the thermostat ("heat recipient") is larger ...
2
votes
1answer
297 views

Changed O2 Sensor and my mileage went down

I changed the O2 sensor on my 97 Mazda 323 BA 1.8L BP DOCH Lantis and my mileage actually went down. The car had the original sensor in it, with about 200,000 kilometers on it and I replaced it with ...
-1
votes
2answers
554 views

Why are American cars less efficient compared to european European/Japan cars [closed]

A normal average European car has a engine with less than a 2.0 liter engine which consumes 1 litre of fuel in 18-22 km. A normal average American car has a engine at least a 2.5 liter engine and ...
4
votes
2answers
178 views

How much improvement from replacing an O2 sensor?

I'm currently getting about 19.6 mpg city in my 97 Mazda Lantis 323 / Protege 1.8L. According to fuelly a car like this should be getting around 26 mpg. The car has about 127k miles on it, and I ...
5
votes
6answers
4k views

What can cause a car to consume more fuel?

All over my long driver career, I had 4 cars (5 years). I always compare my fuel consumption with other people who have the same car. 3 times out of 4, I found out that my cars were consuming more ...
4
votes
3answers
8k views

Is the ECON button just a placebo?

I recently bought a Honda Civic that had this in the car: I have no idea what it does, and how it's supposed to help. Even Honda's website is ambiguous, just using a lot of fuzzy words to describe ...
2
votes
1answer
111 views

Automatic Throttle Body and TPS on a Manual

This is in continuation to my question Fast Idle and High Fuel Consumption. I just bought a Manual 97 Mazda Lantis 323 1.8L DOHC 16 Valve BP ( apparently called a Protege in the US ) which has a fast ...
1
vote
3answers
279 views

Fast Idle and High Fuel Consumption

I just bought a Manual 97 Mazda Lantis 323 1.8L DOHC 16 Valve BP and I was amazed that it went through 1/4 tank gas ( about 12.5 liters or 3.3 gallons ) in one day after about 60 kilometers / 37 miles ...
1
vote
1answer
235 views

Car stalling in the morning

So I have been dealing with an elusive CE light and some shaking of my car for a while now. For a while it was just shaking occasionally, I thought it was a moisture problem, but that doesn't seem ...
1
vote
5answers
77 views

More air pressure in tyre Vs Mileage

Whenever I inflate my tires to medium/recommended pressure the mileage is better and obviously when it is very low the mileage affected. But I want to know why my mileage affected even if I keep ...
4
votes
2answers
918 views

Is topping up the oil enough of an oil change?

If you use synthetic ester-based oil in a relatively new petrol engine, top it up regularly, and the engine runs very quietly and basically without any noise whatsoever (especially after another top ...
0
votes
3answers
155 views

How to increase fuel economy

What is the normal fuel consumption for carburetor type Toyota 3A engine? My 1986 Toyota Carina AT 150 car gives 11 km/l in city and 14 km/l on highways. How can I increase it more? Please advise.... ...
2
votes
3answers
283 views

Is Petrol usage Proportional to Gas Pedal position

I was wondering about this the other day. Is the petrol usage in the car only influenced by the position of the gas pedal? So for example if I take my foot of the gas and coast for 30 seconds, would ...
1
vote
4answers
1k views

Will a battery reset improve fuel consumption?

I recently bought a used 2003 Opel(Vauxhall) Astra G 1.4. I drove around 2000km's in the last few months (city and highway mixed), and I used about 200 litres of gasoline, which means a 10l/100km ...
-1
votes
1answer
286 views

Why do i have to service my gearless Honda Activa every 2 weeks

I currently own a Honda Activa which is of a 2007 make. After three years during a heavy traffic jam the conveyer belt got heated up and burnt due to continuous acceleration and braking. I got it ...
7
votes
1answer
221 views

What does a healthy spark plug look like?

The spark plug pictured here: Has some black carbon on the underside of the ground electrode and has black carbon on the "base" area below the centre electrode (not pictured). Is this normal and ...
0
votes
1answer
73 views

Using narrower tyres than were fitted as standard, for reduced rolling resistance = > fuel economy

I have had several cars, which have all been "sporty", fuel economy has never been a requirement. Now it is. So I've bought a little 1.2 petrol which gives me 65mpg on the motorway/highway and 40mpg ...
0
votes
1answer
70 views

Can I install nano fuel economizer for carb type toyota 3A engine?

Can I install nano fuel economizer for carb type toyota 3A engine? Will it help to improve fuel consumption of my car without any issue?
0
votes
1answer
219 views

what is the advantage of octane 90 petrol vs octane 95? how it effect to fuel consumtion of a car? [duplicate]

i need to know about advantages of octane 90 petrol VS octane 95 or unleaded. how it effect to fuel consumption of a car?
0
votes
2answers
72 views

Most economical acceleration range

I am designing a GPS based acceleration meter for car. I'm planning to give user some scores based on his various acceleration practices. Not going to the electronics part of GPS, i want to know in ...
1
vote
2answers
499 views

Need to know about spark plug

What is the most suitable spark plug for Toyota 3A engine in Asia? (NGK/Champion/denso/BOSCH and also copper/platinum or iridium) Please explain the differences/advantages between them and how it ...
1
vote
1answer
225 views

“Reserve” on 2009 Ford Fusion SE Range Calculator?

All, I'm trying to calibrate a smartphone fuel consumption application on my vehicle, a 2009 Ford Fusion SE with the I-4 engine. I want to get a "control" varible to compare against the mileage ...
1
vote
0answers
814 views

Fuel Consumption and other Fuel related data from basic OBD-II parameters

I want to know how can i obtain the values of Fuel Consumption, Fuel Economy and other fuel related information from basic OBD-II parameters like Vehicle Speed, RPM, TPS etc. I have noticed that not ...
3
votes
1answer
110 views

Will a 12 V cooler box significantly affect the performance/gas mileage of my car?

I have an Apollo brand 12 Volt Cooler/Warmer, designed to plug in to my car's 12 V cigarette lighter. I am wondering if the power this device uses will significantly affect my car's performance or ...
2
votes
1answer
232 views

KIA Sedona 2003 Diesel Intercooler Turbo Low Fuel Mileage

I have a 2003 a Kia Sedona turbo diesel 2.9L, with intercooler. I am getting 5 km per liter of diesel consumed. I also have to do oil change and ATF replacement. I got the car 3 weeks ago. What are ...
1
vote
1answer
91 views

How different is the injection phase in a BMW M41 Engine in flat terrain vs climbing terrain?

Let's say I am driving in a BMW 318 TDS (gasoil) : on flat terrain, at 70km/h, with only one passenger, at 2000rpm on a climbing terrain, at 70km/h, with 4 passengers and a loaded car at 2000rpm ...
4
votes
5answers
21k views

What to check if fuel consumption is too high?

I think my car is consuming much more fuel than it should, I've compared it to other versions of the same model which have more powerful engines and mine seems to be on the higher end when is supposed ...
0
votes
1answer
107 views

Fuel consumption: Coasting vs in gear without thrust [duplicate]

If you're driving downhill would it be more economical to put the car in neutral and coast, or leave the car in gear and let the wheels drive the engine? Please ignore any safety concerns for this ...
2
votes
2answers
288 views

Trip computer reported MPG with engine remap or chip

A question related to Car average mpg display correctness I suppose, but say if a piggy back chip (e.g. http://www.dieselandpetroltuning.co.uk/) was added to a diesel car with trip computer, would the ...
6
votes
4answers
3k views

Can I improve fuel economy by changing differential’s gear ratio?

I would like to use my Lada Niva for normal road travel, but at 3500 rpm at 100 kph it is not very fuel efficient. I don’t know what the current differential ratio is, but I assume it has been changed ...
2
votes
3answers
48 views

Are L/100km figures reported by the Canadian government attainable?

I'm in the market for a new car, and fuel efficiency is important since I'm commuting 2 hours a day. The EPA and Canadian governments use different measures of fuel efficiency. I don't mean just the ...
4
votes
2answers
949 views

Car average mpg display correctness

I have been wondering about the correctness of the average MPG displays on modern cars. Mine in particular is a Renault Modus. What I did is fill the tank, drive around and then refill the tank to see ...
3
votes
1answer
326 views

Brake Specific Fuel Consumption of 2-stroke vs 4-stroke

How much fuel do various types of engines burn per power output? I'm especially interested in naturally aspirated piston engines, and comparing two-stroke to four-stroke. The wikipedia article gives ...
2
votes
2answers
526 views

Improving fuel economy in high-milage automatic transmission car

Obviously this question is similar to How to improve fuel economy in high-mileage car? except I am asking specifically about automatic transmission car. The car still delivers lots of ...
5
votes
3answers
2k views

Does accelerating faster worsen fuel efficiency?

I've often heard that accelerating harder makes for bad fuel efficiency, but have yet to be given a sound explanation of why. Naturally this makes me question this advice. Now obviously when you ...
4
votes
3answers
1k views

why do engines have so much unused horsepower?

I've looked at the power rating of an engine used in a Humvee (5500 lbs) and was surprised it's only ~190 horsepower, which is exceeded by many 4 door sedans. So an obvious question is why doesn't my ...
0
votes
2answers
856 views

What would cause a 2003 Kia Sedona to have bad fuel economy?

I have 2003 Kia Sedona 2.5 liter AT in good condition. I've replaced some of the old parts with new ones. Both highway and city fuel consumption is bad compared to other cars with same engine ...
8
votes
2answers
2k views

Low power, bad gas mileage, smelly exhaust after engine work

My 92 Civic has had low power (need to use at least one gear lower than usual to get the same power) and has been getting bad gas mileage (15-25mpg vs 32-42 mpg usual) since I replaced the head ...
4
votes
2answers
287 views

When do engine type and mileage of a car affect pricing?

I'm currently designing a customer relationship management tool for auto shop owners and was wondering: Does engine type or the odometer value of a car ever affect pricing for a customer? What ...
2
votes
5answers
5k views

How to save fuel on downhill slopes on a motorcycle: clutch or neutral?

I have a two wheeler i.e. bike (Honda company, four stroke) which has four gear. While driving my bike, when I come to downhill slopes, I shift the motorcycle to neutral to save the fuel. (The slopes ...
2
votes
3answers
86 views

Alternate fuel for motor cyce

In some countries, Government mixes ethanol with petrol & diesel and distributes it to their consumers. This will save some of their imports. My question is Can I blend petrol with Zatropha ...
4
votes
2answers
6k views

Why does my engine perform poorly and get bad gas mileage after using fuel injector cleaner?

At the advice of someone at a local auto parts shop, I poured a bottle of fuel injector cleaner into my gas tank. This happened around the same time that I had a brake job done and rotated my tires. ...