If there is one thing that will make you jump in your driver’s seat, then it is the sound of your (or any) car backfiring. That is the kind of jolt that can definitely get the heart racing. Once you calm down, you’ll start to wonder, “Why is my car backfiring?” These might be the reasons:
The Timing is Incorrect
When you talk about an engine’s timing, it is all about the sparks firing from a spark plug to ignite the fuel and air mixture properly. That is the basics of ignition timing. If that timing “skips a beat,” then it can cause the backfire explosion of the air and fuel mixture that is in the intake manifold. That mixture “fires” out of the carburetor or injection intake causing the bang.
Bad Plug Wires
Why would a spark plug fire at the wrong time? It could be that their wires got crossed or they weren’t installed properly. It is the same condition created when the timing is off.
Vacuum Hose Leakage
There are a lot of hoses running through your car. When excess air builds in the intake manifold from a leaking vacuum home then the air-fuel ratio will be out of whack. This causes excess air to be mixed to the fuel creating the “lean running condition” and resulting in a backfire.
Faulty Computer Signals
All of these fuel-air mixtures need to be carefully regulated in order for the car to run smoothly. Modern cars depend on onboard computer sensors to monitor those ratios. If one of those sensors becomes faulty, then the computer will misread the airflow and fuel mixture. Essentially, the computer will screw up and not add enough fuel to the incoming air. The result is a classic pre-ignition backfire.
Weak Fuel Pressure
A fuel pump that is on its last legs or has a clogged fuel filter can also mess with the mixtures and ratios. This can be another “perfect engine storm” that creates the lean running condition.
Hopefully, if your car backfires, then you’ll be able to diagnose a fast fix. You don’t want this to be a recurring condition.