Tip & How-To about Honda Accord

Poor fuel economy, mileage

What should I do if my fuel economy is excessively low on my vehicle?

If your fuel economy is excessively low on your vehicle, it may need to be serviced or repaired. You may want to contact your local dealer or a reputable repair facility to check your vehicle. The following are some of the diagnostic checks a mechanic will typically conduct for poor mpg on your Honda Prelude:

Perform "On-Board Diagnostic System Check" for diagnostic trouble codes (sensors or actuators which may be malfunctioning)
Check for dragging brakes
Check transmission shift patterns for slipping, use of all gears, lock-up operation
Check ignition timing
Check owner's driving habits including A/C usage, hard accelerations, carrying heavy loads
Check emission control system
Check vacuum hoses for leaks, kinks, proper routing
Check tire pressure
Check fuel type, quality, and alcohol content
Check fuel pressure and fuel system for leaks
Check air cleaner element
Check coolant level
Check ignition system for wet plugs, cracks, wear, improper gap, burned electrodes, or heavy deposits, cracking or improperly connected ignition wires
Check for proper calibration of speedometer
In extreme cases, there may be engine problems such as poor compression or faulty fuel injectors. Replacing fuel injectors on any vehicle is not for the beginner or backyard tech. It is advisable to take it to the Dealership or a repair shop that you trust.

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1 Answer

uses excessive amount of gas

run fault codes to find faulty sensors. Then there are dozens of reasons for a thirsty engine so I will list a few
1 tyre size and inflation
2 driver habits
3 blocked exhaust (cat converter faulty)
4ignition timing
5 fuel injectors
6 load in the vehicle
7 load on top of the vehicle
9 speed
10 area= Hilly --city -- stop start
11 if carby check for faulty power valve.
12dragging brakes / pads
13 fuel pressure
14 not engaging OD in automatic box
15 drive line wear
16 wheel alignment
these are just a few and a combination of any will knock considerable mileage off the economy.

Mar 19, 2014 | 2001 Buick Century

1 Answer

What does acam or crankshaft sensor do

  • The crankshaft position sensor identifies position of the crankshaft to the ignition control module (ICM), engine control module (ECM) or powertrain control module (PCM)
  • When not replaced, vehicle could experience no- or hard start, long crank time, misfire, lack of power, excessive hydrocarbons in oil, spark plug fouling, catalytic converter failure, poor fuel economy, CEL/MIL illumination or intermittent shutdown.
  • The camshaft position sensor identifies position of the camshaft to the ignition control module (ICM), engine control module (ECM) or powertrain control module (PCM)
  • When not replaced, vehicle could experience no- or hard start, long crank time, misfire, lack of power, excessive hydrocarbons in oil, spark plug fouling, catalytic converter failure, poor fuel economy, CEL/MIL illumination or intermittent shutdown
  • Jul 24, 2012 | Cars & Trucks

    1 Answer

    lost gas milage

    There are literally dozens of potential causes for a decrease in fuel economy - many of them will also cause other symptoms with the way the vehicle operates, which can be helpful in diagnosing the problem. Some of the more common ones are:

    * Fuel/Intake System Restrictions - Dirty air filters, fuel filters, and fuel injectors make your engine work harder to generate the same amount of power at the wheels, thus wasting more of its own energy and reducing mileage. This is probably the most common cause of gradual fuel economy loss because, unless the problem is severe, computer controls can usually compensate such that the average driver doesn't notice any issues. This is why it's important to stick to maintenance schedules, even if it seems unnecessary at the time.

    * Engine Management Problems - Modern vehicles rely heavily on computer controls to "fine-tune" the engine in real time for maximum efficiency; an assortment of sensors monitor various engine parameters and feed data to the computer that allow it to make adjustments as conditions warrant. Most of these sensors are subjected to some "hostility" during operation (high temperatures, corrosive gases, contaminants, mechanical wear, etc) and do occasionally fail, preventing the computer from correctly doing its job and consequently reducing efficiency. Similarly, the computer in turn uses some electronic and electromechanical devices to actually control the engine, which can suffer the same fate. Problems of this type will almost always turn the Check Engine light on and cause additional driveability issues (rough idle, poor acceleration, stalling, etc).

    * Wheel-End Problems - Low tire pressure is another common cause of low fuel mileage. Low pressure allows a greater portion of the tire tread to contact the road, increasing friction and sapping power (it also causes accelerated and abnormal tire wear). Wheel alignment problems cause similar issues by forcing tires to "drag" across the pavement to some degree, rather than roll smoothly. Less commonly, malfunctioning braking or all-wheel drive systems can cause additional drag at one or more wheels, wasting power.

    * Environmental Issues - The environment and manner in which a vehicle is operated can have a big impact on its fuel economy that you might not consider unless you stop to think about it. Your mileage may decrease in snow, for example, because you spend more time in stop-and go conditions and in low gear, or in the summer months if you drive more aggressively. Changes in overall driving habits (going from mostly highway to lots of city driving) can also play a big role.

    * "Parasitic" Problems - The engine is ultimately the source of all power used by every system in the vehicle, and as such, any part of the vehicle operating in an inefficient manner has the potential to reduce fuel economy. Clutch/transmission slippage, for example, can cause a dramatic loss in fuel economy, as can regenerative braking malfunctions in hybrid vehicles. Engine accessory problems (water pumps, alternators, etc) can put fuel-wasting drag on the engine, as can internal mechanical problems of the engine itself (these types of problems usually make themselves apparent in other ways - a bad alternator will cause electrical problems or make noise, for example). Even body damage or modifications can increase wind drag, decreasing fuel economy.

    One last thing to keep in mind: it is entirely possible for several causes to simultaneously contribute slight effects which all add together to cause a more pronounced problem; hence, it isn't always possible to pinpoint a single "silver bullet" that will cure poor fuel economy, especially in higher-mileage vehicles.

    Feb 20, 2011 | 1993 Geo Storm

    1 Answer

    hyundai coupe excessive fuel consumption

    Unless the Check Engine Light is ON, there is no vehicle-related issue to fuel consumption. The computer will deliver the exact amount of fuel needed to satisfy the demands placed on the engine, using input from a large variety of sensors, including the accelerator pedal position sensor. Fuel economy estimates in the USA are just that, estimates, derived from a chemical analysis of emissions, and not actual driving. And no vehicle ever hits those numbers.

    There are numerous outside factors that have a negative impact on fuel economy:
    Vehicle maintenance, driving conditions (stop & go driving KILLS fuel economy), accelerator pedal usage, overall vehicle speeds, loads carried, etc.

    Remember, the more you use the gas pedal, the more you use the gas station!

    Feb 09, 2010 | 1999 Hyundai Accent

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