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Q: After it warms up it floods out when you give it gas

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I changed out both oxygen censors yesterday. Same thing happened. After driving for 15 minutes when I would give it gas it started cutting out. My husband said it's burning rich. When this happens there is a sulfur smell. What can I do next. This is our only vehicle

My car has 230000 miles.
My car has a manual transmission.

A: The smell of gas is most commonly due to a ...

The smell of gas is most commonly due to a misfire. A misfire is when the fuel sprayed into the cylinder is not burned, then it is pumped out the tailpipe. Raw fuel is pumped out the tailpipe through the catalytic converter. Converters create that sulfur smell when they are injected with too much fuel. If your Check Engine Light is flashing, you should not drive your car until this problem is repaired. A flashing Check Engine Light is letting you know too much fuel is in the catalytic converter and a risk of fire is present. If you have ever driven by a burning car on the side of the road, it was probably the result of a catalytic converter fire. So don’t drive it with a flashing Check Engine Light.

Either your car is going into wide open throttle, which means the fuel injectors are open 100% of the time, or you have a misfire. This can be hard to determine with symptoms such as this. Misfires are commonly a result of ignition system problems and excessive fuel or a rich condition is the result of the PCM deciding full throttle has been requested. This is less common and misfires will produce more fuel out the tailpipe than a true rich condition. Most cars aren’t capable of injecting so much fuel that the car will die. They will typically just use more fuel with a heavy black stain inside the tailpipe. But usually they will run very well because more fuel means more power.

First thing to do is to determine if it is misfiring or actually running to rich. If your not sure how to do this, I recommend getting your stalling issue inspected by a certified technician, such as one from YourMechanic.

Good luck!

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