VW Fox Diesel Running Rich with Power Loss & Jerking

Had the exact same symptoms on my 2010 VW Polo diesel. The rough running, excessive fuel consumption and jerky acceleration pointed directly to faulty fuel injectors. Running too rich means unburned fuel was going through the catalytic converter, which could have led to bigger problems if left unchecked. The diagnostic showed three injectors needed replacement. This is a serious issue requiring specialized equipment and expertise. Not something for DIY unless you have professional tools and deep technical knowledge. The fuel injectors are critical for proper fuel atomization and engine performance. Before replacing injectors, worth checking simpler things first: Air filter condition, Fuel filter maintenance history, Basic diagnostic scan for error codes The symptoms closely match classic injector failure. The jerky acceleration happens because failing injectors cant deliver precise fuel amounts. Once fixed, fuel economy returned to normal and the engine ran smooth again. If these symptoms sound familiar, get it checked soon. Continuing to drive with faulty injectors risks damaging other engine components and the catalytic converter.

Thanks for sharing your experience with the Polo. That injector replacement sounds exactly like what my Fox needs based on the same symptoms. The check engine light triggered me to scan for codes and they also pointed to injection system problems. The intake manifold was actually pretty dirty too when I checked. Did the repair solve all the issues completely? Would help to know what you paid for the full job and if any other problems came up in the months after fixing the fuel injectors.

Thanks for asking about the follow-up. The injector replacement completely resolved the rich mixture problems in my Polo. Total cost was 515€ for parts and labor, worth every cent considering how much fuel I was wasting before. The check engine light disappeared right after the repair and the engine runs perfectly smooth now. Fuel economy went back to normal levels within the first tank. The jerky acceleration completely went away once the new injector was properly delivering the correct amount of fuel. No issues whatsoever in the 6 months since the repair. The mechanic also cleaned the intake manifold while doing the job, which helped restore proper airflow. The spark plugs showed no carbon buildup during a recent inspection, confirming the fuel mixture is now correct. My advice, get it fixed soon. Running too rich can damage multiple engine components if left unchecked. The symptoms you describe are textbook injection system problems, just like mine were.

I finally got the car fixed last week and wanted to share the outcome. Took it to a different mechanic who specializes in VW diesels. The air-fuel ratio was way off due to two faulty injectors, exactly as suggested here. The total repair came to 480€ including parts and labor. They also found the air filter was pretty clogged which contributed to the rich fuel mixture. Had them replace that too while they were at it. The oxygen sensor readings are now perfect and the check engine light is finally off. Engine runs smooth as silk, no more jerky acceleration or excessive fuel consumption. Already seeing much better mileage after just one tank. Really glad I did not wait longer. The mechanic showed me how the old injectors were causing unburned fuel to go through the system. Could have caused some serious damage if left unfixed. For anyone with similar symptoms, definitely worth getting the injection system checked out properly. The diagnostic fees are worth it to prevent bigger problems down the road.