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Q: Fuel consumption is high

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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.

A: Hi and thanks for your question. In order t...

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.

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