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10

In a word: No. To add more to it: Absolutely Not. There is one huge thing which you have not taken into account. That being carbon which deposits from the air/fuel mixture burning process. Where does it go? Right into the oil (among other places). A small amount of blow by occurs which also forces this mixture down into the crank case. Now you have it in ...


9

You are driving a Saturn S-Series (My car for the last 8 years, which I am very happy to have.) You should definitely have much higher fuel economy. (19.6mpg is what you have. 33+mpg is easily achieved.) I would hardly be surprised if it is the ECTS (engine coolant temperature sensor.) These plastic temperature gauges fail with about 100% certainty. This ...


8

As DucatiKiller notes, coasting downhill in neutral is usually considered unsafe, as it increases the chances of overheating your brakes. It is also illegal in many jurisdictions. Questions about driving techniques are generally off topic here, but you do have a question about how engines work that I think is (maybe marginally) appropriate: why do you get ...


7

The most common causes (aside from poor driving habits) are bad timing bad sparkplugs low octane fuel* malfunctioning coolant temperature sensor blocked catalytic converter(s) malfunctioning MAP/MAF sensors driving with the parking brake engaged** having aftermarket wings on the car. tyres not inflated to the recommended pressure and a few others I can't ...


6

The ECON button is not a placebo, though the wording from that specific web page is a bit vague. The key is that the ECON button and the Eco-Assist system are two separate things. According to Honda, pressing the ECON button configures your car to improve mileage at the cost of performance. Turning it off will improve power and reduce mileage, which you ...


5

I doubt you're going to be able to have someone put a number on this. I'm betting you also know that just because no error was thrown, it doesn't mean that the sensor isn't impacting performance. Lifehacker notes that replacing them could improve mileage "up to 15%." As @BobCross mentioned, "most people wouldn't consider it worth their time to do the ...


5

tl;dr: Ambient air temperature should generally not interfere with engine efficiency or fuel consumption, but will affect overall power output. Do not confuse efficiency with power output. These are two separate things. When your intake charge is more dense, you can throw more fuel at it and creates more power. (NOTE: The idea for the engine management ...


5

The oil stuff is more than likely caused from what the intake pulls out of the crank case through the PCV. If you can get a hold of a couple cans of Seafoam, this should take care of the residue about as easy as you can do it without taking the engine apart. Use the rubber hose to the right of the photo to introduce it into your system. As an engine gets ...


5

Over on the linked question, I talked about how engine braking works to reduce fuel consumption at a high level: Coasting: nothing much. The transmission is effectively disengaged (it's more complicated than that but it's a reasonable approximation). The engine is idling - burning fuel to keep itself spinning. Engine braking: the transmission is ...


4

Recommended values give you the handling and tire wear that the manufacturer intends for the vehicle. If you increase above that, the contact patch decreases, giving better gas mileage, but you start sacrificing handling and causing abnormal tire wear.


4

I think you need to do a throttle position sensor recalibration (reset). (NOTE: I will post several different adjustment versions. I believe the top one is what you need (for a K8 engine), but will include another four depending on your engine.) To do this for your vehicle you need to follow the steps below, depending on whether it is a stick/auto and ...


4

As @LynnCrumbling stated, this would be hard to put a number on, mainly because it depends on too many factors. This is what I can tell you. When O2 sensors get old, they don't necessarily go bad, what they do is get lazy. When a good O2 sensor is doing its thing, if you were to look at the readings from it, the numbers go all over the place, from top of the ...


4

Disconnect your battery to reset your ECU. It won't hurt, and is probably the cheapest and easiest thing you can try. 30 minutes is usually enough. There are other theories as to why your mileage went down, but I think you're on the right track thinking the ECU hasn't learned to use the new data correctly. I am thinking that because your new 02 sensor is ...


4

This is an average of the figures for constant speed (highway) driving in top gear and city/traffic driving with lots of gear shifts. The ratio is usually 50/50 so they'll measure e.g. 100 miles of highway driving, then 100miles of city driving, add the figures together and divide by two to get the combined average. Though to get those same figures, you're ...


4

The generalized statements about the gaps being too small causing insufficient burn and too wide having a weak spark are spot on. As you widen the gap, you need to increase voltage to cover the gap. Also, as you increase pressure at the top of the compression cycle, you'll need to either increase the voltage output to the spark plug and/or reduce the gap of ...


4

Background This is a common issue with shim and bucket valve trains. As the valves are getting worn into the head a small groove is beat into the valve face after opening and closing so many times. As the valve pushes up into the head it takes up clearance between the cam lobe and the bucket which the cam lobe depresses to push the valve in and open it to ...


4

Mileage of a car is based on a ton of factors but since you are concerned with a specific speed range it comes down to one thing Air resistance. Air resistance: There is very minimal difference in the air viscosity between 70 to 90 kmph but when you go more than 110 the air starts to get thick , simply put , if your car's aerodynamics are optimum to handle ...


3

Where you drive your car has a significant impact on the fuel economy. If you drive mostly on highways and other roads with high speed limits and no stop signs or stop lights you will have a high fuel economy, while if you mostly engage in "city driving", that is, roads with lots of stop signs, stop lights, and heavy traffic, you will have a lower fuel ...


3

I don't know what that specific button does, but I can tell you what similar buttons in other cars do: they retard your throttle response so that your car feels more sluggish. This means that when you step on the gas, it does not cause the throttle to open quite as much, making your drive smoother and more fuel efficient. Conversely, a "sport" button would ...


3

Your logic is way off. You should change your oil and filter at the manufacturers recommended intervals, with an oil of the manufacturers specification. The manufacturers cover many many miles under many differant conditions to decide a specification and in most circumstances the specification cannot be bettered for the intended use of the vehicle.


3

Yes, a reset could work, if the problem is that the ECU is used to the previous driver's driving style and his style was vastly different to your's. But it could also just be the way you drive. Do you drive more like Morgan Freeman or Vin Diesel? These cars are quite heavy on the juice in city driving. With mine, I get about 7.5l/100km on the highway going ...


3

Lots of things influence fuel consumption, actual pedal position being probably the strongest. The engine's rotational speed has SOME influence, but not nearly as much as pedal position... and a lot of the reason that the engine's speed has influence is because ignition timing will be different at different engine speeds (among other secondary influences), ...


3

Paulster2's comment on your post is absolutely correct. The difference between diesel and petrol is so huge, it completely overshadows the differences between cars in various regions. That said, there is historical precedence for different typical power/fuel consumption figures in these regions. The US has long had very cheap fuel, cheap land and extensive ...


3

Considering on this website they say you can figure out the amount of CO2 emissions per km based on the fuel mileage, I'd suggest they are saying the rate of emissions is proportional to the MPG (given their constant). This makes sense to me because there are so many carbon atoms in a gallon of gas. When burnt (correctly), the CO2 emissions are going to be ...


2

There was a thread on here entitled Fuel Consumption and other Fuel related data from basic OBD-II parameters where the author was concerned about fuel consumption. While the question was never "answered", there was an article posted which sheds light on your question. It is a PDF entitled Estimation of Fuel Consumption using In-Vehicle Parameters, by Min ...


2

I live in Canada and I can tell you the wear on starting an engine is greater than idling for a few minutes, guaranteed, especially since here in the winter it can only take 20-30 minutes for your engine to drop from full operating temp down to room temperature if it isn't running, and cold starting an engine means less viscous oil in the crankcase as well ...


2

I have a 2013 Honda Civic EX Sedan. The ECON mode, from my research and personal experience with my car, does the following: changes the shift pattern of the transmission to maximize mpg by limiting downshifts unless you "floor it", reduces the A/C compressor operation and A/C fan to conserve mpg, changes the throttle response to maximize mpg and adjusts ...


2

Other common thing that causes high fuel consumption is imperfect work of brake system. Brake pistons and pads should travel freely... Just take your lifting jack and rotate the wheels right after applying brake: wheel should be fully released with no delay. UPD I suppose every sticking brake caliper adds 1 liter per 100 km.


2

The tube that draws fuel out of the tank is not at the absolute lowest point of the tank. This means that when the fuel runs almost dry, the last few drops won't be picked up. That could be because of airlocking or there is a contour in the tank that leaves a small amount of fuel inaccessible. In your case, there is 1.2l of unaccessible fuel. This ...


2

Short answer, ALL of the convienences mentioned above reduce the fuel economy of a car, any electircal system you use will affect the fuel economy,to understand why we must know how these systems are powerd exactly, its not as as you think. The battery operates when you start the car, the moment the car is started the , the power to run the electric ...



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