Why does my VW Jetta have a bad fuel injector?
Your Volkswagen Jetta’s fuel injection system atomizes the fuel into a fine mist. If a fuel injector is not operating properly, it will either let too much or too little fuel into the combustion chamber relative to the amount of air. There are many reasons why a fuel injector may go bad, as well as different symptoms relative to how they went bad.
What are the O2 sensors on a VW Jetta?
The oxygen sensors that are equipped in your Volkswagen Jetta are responsible for monitoring the exhaust to help the ECU determine the correct air/fuel mixture. Of all the sensors equipped in your vehicle, the O2 sensors may have it the hardest. They deal with super hot exhaust that can cover them in deposits that can leave them ineffective.
Why is my VW Jetta running rough at idle?
Really, your Jetta will be running rougher at any RPM, but a misfire will be most pronounced at idle. Spark Plug Wires – While not every model and engine combination of vehicles today comes with spark plug wires (a lot are now coil on plug), if your Jetta happens to have them, they can go bad and cause a rough idle.
Why is my VW Jetta losing so much power?
A backfiring or smoking exhaust can indicate either too much fuel or too little spark, both of which can bring about power loss. A backfire occurs when the fuel-air mixture does not fully ignite in the combustion chamber, but instead pops off elsewhere in the system.
What happens if a coil pack goes bad on a Jetta?
These packs are fired by the engines computer at exactly the right time to provide the optimal ignition timing. If a coil pack goes bad, it’ll cause a misfire and rough idle condition. Really, your Jetta will be running rougher at any RPM, but a misfire will be most pronounced at idle.