VW Spacefox Rough Running & Lean Condition Issues

I dealt with nearly identical symptoms on my 2008 VW Golf with the 1.6L gasoline engine. Based on my moderate experience with fuel system issues, these symptoms strongly point to problematic fuel injectors. Initially, I noticed similar performance issues, sluggish acceleration, rough idling, and the engine running lean. The check engine light came on, and diagnostic testing confirmed issues with the fuel delivery system. The workshop found that one fuel injector was completely clogged and another was partially blocked, causing uneven fuel distribution. They recommended replacing all fuel injectors as a set to ensure balanced performance. The repair included: Complete fuel injector set replacement, Cleaning of the fuel rail, Diagnostic testing and adjustment of the air-fuel ratio, Final performance check Total cost came to 515€ for parts and labor. Since the repair, the engine has run smoothly with no further issues. Could you share: Engine size and type, Current mileage, When the symptoms first appeared, Whether you notice the issues more during cold starts or when the engine is warm, Any fuel consumption changes This information would help confirm if your situation matches what I experienced with the faulty injectors.

Just had my latest service done 2 weeks ago, and the issues started shortly after. The workshop did clean the throttle body and intake manifold during service, which makes me wonder if something was overlooked. The oxygen sensor seems like a likely culprit, as my had similar lean condition symptoms that turned out to be a failing O2 sensor. The EGR valve on these engines can also cause similar issues when it gets carbon buildup. My gut says it might be simpler than a complete fuel injector replacement. Could we be looking at something that was disturbed during the recent service? The timing seems suspicious. The lean condition doesnt seem to improve as the engine warms up, which points more toward a sensor or vacuum issue rather than fuel delivery problems. Has anyone checked for vacuum leaks after servicing these models?

Since my previous repair with the fuel injectors, I have learned quite a bit about these issues. Given that your problems started after the service, I agree this likely points to something different than my initial injector diagnosis. After reading about your service timing, this strongly reminds me of a similar situation I faced with my Golf. A vacuum leak developed right after throttle body cleaning, the technician had not properly reseated one of the intake manifold gaskets. The symptoms were nearly identical to what you describe. The check engine light and lean condition in my case were actually triggered by a small vacuum leak where the intake manifold connects to the throttle body. The cleaning process sometimes requires disconnecting several components, and proper reassembly is critical. A quick check you can do: Listen for any hissing sounds around the throttle body and intake manifold while the engine idles. In my case, this revealed the leak location before any expensive parts replacement was needed. If not a vacuum leak, the oxygen sensor is certainly worth investigating since it directly affects fuel mixture calculations. When checking mine, the spark plugs showed signs of lean operation, they were unusually white, which helped confirm the diagnosis. Suggest having the workshop: 1. Perform a thorough vacuum leak test 2. Verify all connections were properly reassembled 3. Check oxygen sensor readings 4. Inspect spark plugs for lean condition indicators The repair in my case only cost 85€ for a new gasket and labor, much less than my previous fuel injector experience.

Thank you for sharing that additional context about the recent service. My 1.6L engine has done about 180,000km, and these symptoms started appearing about 3 weeks ago. The fuel consumption has increased by roughly 15% since the issues began. You raise a very logical point about the service timing. The intake manifold work could definitely have disturbed something. I notice the symptoms consistently whether cold or warm, which does align more with your vacuum leak theory than with my initial fuel injector concerns. This morning I did the suggested check for hissing sounds and noticed some subtle whistling near where the throttle body connects to the intake manifold. Also found the engine seems to run slightly better if I manually adjust the throttle position, which might indicate a vacuum issue. I will have the workshop focus first on vacuum testing and checking all the post-service connections before looking at more expensive components. Will also request they verify the oxygen sensor readings since a faulty O2 sensor could trigger similar symptoms with the air-fuel ratio running lean. The possibility of a simple gasket issue causing all this would be a relief compared to needing new fuel injectors. Will update once the workshop does their inspection. Thanks for helping narrow down the likely causes.