VW Virtus MAP Sensor Issues, Owner Seeks Confirmation

I had a very similar issue with my 2017 VW Polo, and being someone with moderate car repair experience, I initially tried diagnosing it myself using a basic OBD scanner. The symptoms you describe match exactly what I experienced, power loss, poor acceleration, and reduced fuel efficiency. The manifold pressure readings were inconsistent, which pointed to either a faulty MAP sensor or a vacuum leak. After some frustration with self-diagnosis, I took it to a workshop where they performed a smoke test. This revealed a significant vacuum leak in the intake manifold gasket, not actually a failed MAP sensor as initially suspected. The pressure sensor was reading incorrectly because of the leak, triggering the check engine light. The total repair cost was 235€, which included diagnostic testing, replacing the gasket, and checking the MAP sensor functionality after the repair. Everything returned to normal after fixing the vacuum leak. Before suggesting specific solutions, could you share: Have you scanned for error codes? Does the engine idle roughly? Can you hear any hissing sounds around the engine bay? What engine size does your Virtus have? This information would help determine if your issue is similar to what I experienced or if its truly a MAP sensor failure.

Last service was at 20000km and Im currently at 21790km. The OBD scan showed error code P0106 related to the MAP sensor circuit performance. The engine idles fine, and I havent noticed any hissing sounds that would indicate vacuum leaks. The car runs really rough specifically during acceleration. I checked the intake manifold connections, but everything appears secure. The automotive sensor readings from my scanner show erratic manifold pressure values, jumping between extremes during normal driving. Initially thought it might be a simple vacuum issue like yours, but the consistent pressure sensor readings at idle make me think its the MAP sensor itself failing. The rough acceleration and power loss started gradually over the past two weeks, getting noticeably worse in the last few days. Would you recommend going straight for the MAP sensor replacement or should I still get the smoke test done first?

Thanks for providing those details, quite different from my vacuum leak case. The P0106 code with the manifold pressure sensor showing erratic readings during acceleration but stable at idle strongly suggests a MAP sensor failure rather than a vacuum issue. On my Polo, when I had the vacuum leak, the manifold sensor readings were inconsistent even at idle. The fact your readings are only erratic during acceleration, combined with the specific error code, points more clearly to sensor failure than my situation did. While a smoke test wouldnt hurt, the symptoms really align with a faulty MAP sensor. The gradual onset of symptoms is also typical of sensor degradation. When my manifold pressure issues were caused by the vacuum leak, the symptoms appeared more suddenly. Since your car is relatively new with low mileage, Id suggest: 1. Verify the MAP sensor connector is fully seated and clean 2. If that checks out, replace the MAP sensor 3. Only pursue further diagnostics if the new sensor doesnt resolve the issue Total repair cost should be around 150€-200€ including parts and labor, significantly less than what I ended up paying for my vacuum leak repair. Would you like details on the MAP sensor replacement process? Its actually a fairly straightforward job if youre comfortable with basic repairs.

Your symptoms and error code are quite different from what I initially suspected. Since my vehicle has such low mileage at 21790km, I want to ensure we're taking the right approach. The P0106 code combined with those erratic manifold pressure readings during acceleration does seem to point strongly toward MAP sensor failure rather than a vacuum leak. The engine performance issues are definitely worse during acceleration, while everything runs smoothly at idle. My intake manifold connections all look good, and the absence of hissing sounds makes me more confident its the pressure sensor itself rather than a vacuum problem. Based on your experience and the quoted repair costs, I think Ill start with having the MAP sensor replaced rather than going through extensive diagnostics first. The consistent symptoms and error codes make a pretty clear case. If the new automotive sensor doesnt fix the issue, then Ill consider getting the smoke test done as a backup plan. Could you share the specific steps for MAP sensor replacement? While I might still take it to a shop, Id like to understand the repair process better. Also, did you notice immediate improvement in engine performance after your repairs were completed?