Use for questions related to fuel economy.

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5
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1answer
45 views

Why does my 2005 Mitsubishi Pajero use excessive amounts of fuel?

I have a Wagon with excessive fuel consumption. It's using 30 litres of petrol per 100 ks. I have seen many mechanics who can't find the problem. I know it has good intake and no exhaust problems. ...
5
votes
0answers
73 views

fuel consumption is high

My VW Golf 3 is over-consuming fuel, I use 10 liters for 45km, My mechanic ask me to change the automatic gear-box because it is not selecting gear above gear 3 I change the automatic gear-box but ...
5
votes
0answers
511 views

What causes more gas consumption - Idling with AC or Heat? [duplicate]

So I have begun doing some research on the effects of idling. So my question is, does idling with the AC or heater on affect how much gas is given off? If possible, please give the percent of extra ...
4
votes
5answers
8k 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 ...
4
votes
5answers
892 views

Can I save money using E85 in my flexible fuel vehicle?

Where E85 Ethanol is available (not very common), the price per gallon is often lower than regular unleaded gasoline. Though I've read that fuel economy is commonly reduced by 20% or more, when using ...
4
votes
2answers
1k 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 ...
4
votes
3answers
114 views

How would a bad barometric reading affect gas mileage?

My wife drives an '08 Hyundai Azera Limited 3.8L with ~79k miles. Over the past few months she has been complaining that the gas mileage has gone down. Normal around town driving was getting us ~19.6 ...
4
votes
5answers
40k 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 ...
4
votes
3answers
14k views

Effect of loss of fuel tank vapours on mileage

Are there any estimates available on how much fuel you can expect to lose from a fuel tank that is leaking vapours? Leaking vapours would be caused by cracked/missing evaporative emissions hoses, a ...
4
votes
1answer
50 views

How can vehicles run on E?

Sorry if this topic is too open ended I'm new to this site. I am studying engines and how they work and I keep wondering, how do cars with no gas still manage to run for a few extra miles? If you ...
4
votes
1answer
58 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?
4
votes
2answers
2k 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 ...
4
votes
1answer
232 views

How much mpg am I losing with different inflated tires?

I have the front passenger side and rear driver side tires at 34 psi. The other two wheels are around 28. How much is this affecting the mileage on the car? It is a 2004 Cadillac SRX V8, and the ...
4
votes
1answer
79 views

Calculating AFR using injector flow rate and mass air flow

Is injector flow rate = Mass fuel flow? If so then AFR = MAF/Injector flow rate. Can someone please confirm this?
4
votes
2answers
639 views

How much fuel does it take to start an engine?

I appreciate this is a question that can't be answered in facts and figures, so I'm after a general idea. I drive a 1986 Supra, which has a modest 2.8-litre engine. I often shut the engine off while ...
4
votes
2answers
287 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 ...
4
votes
1answer
138 views

2014 Nissan Pathfinder decreasing fuel economy

I purchased a slightly-used 2014 Nissan Pathfinder in January 2015 and have been using it to commute to work (almost exclusively, with the exception of the occasional trip). It currently has 41,000 ...
4
votes
2answers
57 views

Fuel Economy Gauge Modification

I have a little digital screen in my dash that re-evaluates my average fuel consumption (L/100km) every thirty seconds. How can I modify this to increase the reporting frequency? Preferably, at least ...
4
votes
1answer
215 views

Fuel efficiency and volumetric efficiency

I was reading about the better volumetric efficiency of DOHC engines as compared to SOHC engine and was wondering if fuel efficiency is directly related to volumetric efficiency.
4
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0answers
38 views

Integrating Fast OBD Readings and GPS

I'm working on a project to look at fuel consumption on different roads and I need the OBD reader to log the GPS coordinates every time it takes a reading. I'm looking at instantaneous fuel ...
3
votes
1answer
40 views

Can we determine the Cleaning Requirement of Air Filter Using OBD

Many a times, the dealer guy says that the unclean air filter consumes more fuel as compared to clean. So, my question is, is this really related to air filter? If yes, can we determine the case using ...
3
votes
2answers
136 views

Fuel Consumption Paradox

I've been trying different driving styles for a while now, in an effort to reduce my fuel economy and tank range. I've found that I get the best results when racing around, as opposed to driving ...
3
votes
1answer
193 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 ...
3
votes
3answers
54 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 ...
3
votes
3answers
124 views

improving fuel efficiency in a 96 taurus

I have a 1996 Ford Taurus with less than 200,00km on it I don't want to spend too much on it but want to improve the fuel efficiency on it. I do mostly highway driving with a bit of city driving. ...
3
votes
2answers
226 views

Why does my front wheel rotor is heating up more than rear one?

I had been facing high fuel consumption lately. To my surprise I discovered that my front wheel free rotation seems bit restrictive to my rear one even when rear wheel drags chain and two sprockets ...
3
votes
2answers
56 views

1980 Chrysler LeBaron Failed Emissions Test

My 1980 Chrysler LeBaron (V8 318ci) just failed an emissions test. I'm coming from a state without emissions testing to a state that requires it. Specifically, the only part that failed was the ...
2
votes
3answers
595 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 ...
2
votes
2answers
1k 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 ...
2
votes
2answers
334 views

Mileage varies by driving at different speeds

I drive my car a lot. I do lot of experiments with speeds while driving. Following are my observations: Driving at 60 - 70 km/h gives maximum mileage Driving at 70 - 90 km/h gives good mileage ...
2
votes
1answer
412 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 ...
2
votes
3answers
96 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 ...
2
votes
2answers
1k views

How much efficiency is robbed from 'pumping loss,' if any?

I'm specifically referring to the loss due to the pistons pulling air through a mostly closed throttle while cruising at highway speeds in a gasoline engine. To give an example, I've always wondered ...
2
votes
1answer
56 views

Are CO2 emissions proportional to MPG figures?

I was looking at the car tax (VED) system in the UK, as I'm considering buying a new car. I was just wondering, are CO2 emissions always proportional to the MPG figure of a car, both in theory - ...
2
votes
1answer
145 views

Which convenience features in a car affects fuel economy?

I understand that the A/C compressor runs with the engine belt, so it will always uses some HP when engaged, therefore it will have some effect on fuel consumption. What I want to know if there are ...
2
votes
2answers
674 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 ...
2
votes
1answer
844 views

Car stalling in the morning

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 to ...
2
votes
2answers
390 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 ...
2
votes
1answer
69 views

Fuel consumption is bad

I currently own a 2010 Honda Civic 1.8L and a 2012 Honda Jazz(Philippines) / Fit (USA and Japan) 1.5L. I just purchased a second hand Jazz/Fit about 2 weeks ago and the mileage is 32xxx. Btw we use ...
2
votes
2answers
76 views

Fuel gauge not accurate

This does not always happen but it has happened twice in last 6 months. My fuel gage is accurate most of the times but these two times it was showing that there is 10-15% gas in my tank but my car ...
2
votes
2answers
601 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 ...
2
votes
1answer
289 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 ...
2
votes
1answer
364 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 ...
2
votes
2answers
801 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 ...
2
votes
0answers
2k views

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

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 ...
1
vote
5answers
108 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 ...
1
vote
3answers
2k 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
4answers
4k 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
vote
4answers
727 views

Torque App Mileage reliability?

I am using an OBD-II sensor and the Andriod Torque app to look at my fuel economy and see that it shows a whopping 37 MPG for my Mazda 6, 2005 (2.3 Automatic). This seems fishy as some random googling ...
1
vote
3answers
351 views

How to calculate fuel consumption?

If i know the rpm at which the (tachometer indicated) engine is running and the current speed and the engine capacity is there a where to calculate the fuel consumption of the engine? Need not be a ...