Seven Signs Your Air and Fuel Mixture Is Too Rich

We here at Kinetech Motor Werkes have said it a million times: Your European automobile is an amazing piece of machinery. It’s a machine, however, and as with all machines, things can go wrong. Over time, or due to malfunctioning parts, your engine’s air/fuel mixture can get too rich – too much fuel and not enough air. When this happens, you’ll notice one or more of the following seven signs.

1. Check Engine Warning

If your vehicle’s exhaust has too much gas in it, your check engine light will come on. Your vehicle has an Engine Control Unit (ECU), and many sensors send data to it about your vehicle’s exhaust. A rich air/fuel mixture will push excess gas through the exhaust, and the ECU will alert you via the check engine light.

2. Strange Odors

Your automobile’s catalytic converter takes carbon monoxide and turns it into carbon dioxide as well as burns off any excess gas before pushing the exhaust through the system. If there’s too much gas for the converter to handle, you might smell the gas or burning sulfur, which smells a lot like rotten eggs.

3. Poor Fuel Economy

Extra stops to the service station are a sign that your automobile’s engine is burning too much gasoline. If there is too much fuel in the air/fuel mixture, the engine will burn it off. This reduces your vehicle’s fuel economy, and you’ll notice a full tank of gas isn’t lasting as long as it used to, much to your dismay.

4. Engine Performance Problems

Too much fuel in the air/fuel mixture can make your vehicle surge, sputter, or even stall. For example, if the carburetor is set way too rich, it will push enough gas through to the combustion chamber and flood the engine. Your engine power might lag if the engine is being flooded while you’re driving, as well.

5. Emissions Test Failure

As we said above, a rich fuel mixture can overload the catalytic converter. If the overwhelmed converter cannot do its job effectively, you’ll end up with excess carbon monoxide in your vehicle’s exhaust and this will cause your automobile to fail an emissions test. Excess carbon monoxide is a danger to you, too.

6. Engine Idle Trouble

Excess fuel in the engine will make your vehicle idle roughly. This is because the engine is being overloaded by the gasoline and, as discussed above, flooding. Your tachometer might also dance around because the vehicle is struggling to stabilize the RPMs. If it cannot do so, your engine might stall.

7. Part Damage

A rich fuel mixture can damage crucial engine parts. The excess carbon from the fuel can clog the honeycombs inside the catalytic converter and you’ll smell the sulfur odor discussed above. It will also deposit black soot on the spark plugs and deposit excess carbon in the combustion chamber.

We’ve got you covered here at Kinetech Motor Werkes in Indian Trail, NC. We can find out why you’ve got a rich fuel mixture and make adjustments to fix the problem.

Photo by MyrKu from Getty Images via Canva Pro

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