Q: Fuel consumption is high

asked by on

I have replaced the plugs, airfilter, and done a carburettor tuneup with a new carburettor kit, but it still does between 8 to 8.5 km/l on an average. What do i do get a better fuel consumption. I hear this vehicle should do at least 12 km/l.

My car has 5 miles.
My car has a manual transmission.

Hi and thanks for your question. In order to have a good fuel consumption, the fuel to air mixture must be around 14.7 to 1. This is the formula for the air to fuel ratio. Look at the carburetor for any restrictions or leaking fuel. Check the adjustments for that the fuel is about half way and that the air is half way. This will allow the fuel to enter with the proper amount of air into the carburetor.

Also, check to see if there is a vacuum leak on the engine. Take a vacuum gauge and hook it up to the manifold and run the engine at idle. There should be 12 hg of vacuum or more on the gauge to make the engine run. 19 hg to 21 hg is a good vacuum reading that shows the right amount of air being entered into the engine. If you have low vacuum, there could be a vacuum leak or the carburetor may need adjustments.

If you need assistance in troubleshooting your engine, then seek out a professional, preferably a professional from YourMechanic to properly diagnose your car’s high fuel consumption.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Fuel consumption is high

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Vibration on startup - 2004 Nissan Sentra

A lengthy Technical Service Bulletin (TSB) dealing with this issue was published by Nissan in 2006. The TSB outlines a repair procedure for the fuel pump that resolves a known issue with fuel leaking back into the tank instead of...

Q: Stall while idle or coming to a stop replaced IAC MAS and TPS due to codes still same issue

Hello, and thank you for writing in. With the codes you are pulling, and the replacements you have already made, you are likely dealing with an issue pertaining to the the throttle itself, or the idle air control valve gasket....

Q: Gas gauge is not working correctly

If the gauge pointer on the fuel gauge is registering incorrectly, or fluctuating excessively (it can move a little depending on vehicle angle and motion), there could be a problem with the sending unit in the gas tank, the dash...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.