VW Beetle Power Loss: Fuel System Troubles Revealed

Had almost the same issue with my 2010 VW Golf last winter. Being someone with moderate experience working on cars, I initially thought it was related to the mass air flow sensor since the symptoms matched. After monitoring the air-fuel ratio with an OBD scanner, the mechanic found that one of the fuel injectors was failing. The faulty injector was causing uneven fuel distribution, leading to rough running and power loss. They tested the intake manifold and throttle body, which were fine, but the injector was definitely the culprit. The repair cost came to 515€, including parts and labor. Since the fix, the car has been running smoothly with no power issues or check engine lights. Before suggesting more specific solutions, could you share: Current mileage on your Beetle, Any recent maintenance history, Whether you notice any specific conditions when the problem gets worse (cold starts, highway speeds, etc), What codes the check engine light is showing, Any unusual sounds or smells from the engine This information would help determine if your issue matches what I experienced with my Golf.

Last service was at 91000km and showed no issues. Since others suggested checking the fuel injectors, I took it to a shop that tested the injector spray patterns. They found two injectors were partially clogged, causing inconsistent fuel delivery and affecting the air-fuel ratio. They also noticed the oxygen sensor was giving erratic readings, possibly due to carbon buildup. The EGR valve looked clean when inspected, and the throttle body only needed minor cleaning. Looking forward to getting the injectors replaced next week, quoted 680€ for parts and labor. Hoping this resolves the rough running and power loss issues.

Good to hear you got a proper diagnosis. The issue you described matches exactly what I experienced with my Golf, those clogged injectors can definitely cause the lean condition and power problems. The erratic oxygen sensor readings make perfect sense too, as poor fuel atomization from faulty injectors often leads to incomplete combustion and sensor contamination. When I had my injector replaced, the shop recommended cleaning all remaining injectors and replacing the spark plugs at the same time. This comprehensive approach helped ensure optimal fuel delivery and combustion. The extra cost was worth it since it prevented potential issues with the other injectors down the line. The quoted price of 680€ seems reasonable considering they need to replace two injectors. For comparison, my single injector replacement was 515€, so replacing two plus labor is in the right ballpark. One tip from my experience: after the repair, drive the car varying the engine load for about 100km to help the engine control module adapt to the new injectors. This helps optimize the air-fuel ratio and can improve overall performance. Would definitely be interested in hearing how the car runs after the repair. Based on my experience with the same issue, you should notice an immediate improvement in power delivery and smoothness.

I really appreciate everyone's detailed responses and experiences. After getting the two clogged injectors replaced and having the car back for a few days, I can confirm the rough running and power issues are completely resolved. The shop was right about the injectors being the main culprit. The engine now maintains a proper air-fuel ratio and runs smoothly during acceleration. I followed the advice about varying engine loads during the first 100km, and the car definitely feels like it has adapted well. The check engine light has stayed off, and power delivery is consistent again. The total repair ended up at 695€, slightly higher than quoted because they found it necessary to clean the mass air flow sensor while they were working on it. The catalytic converter also got checked and thankfully showed no damage from the previous running conditions. This whole experience taught me that monitoring fuel system maintenance is crucial. Will definitely keep a closer eye on injection system health during future service intervals to prevent similar issues from developing again.