VW Taos Sensor Issues Affect Performance and Economy

I dealt with very similar symptoms on my 2020 VW T-Cross last year. Having some experience with basic car maintenance, I initially thought it was just a dirty sensor, but it turned out to be more complex. The engine performance issues you describe match exactly what I experienced, poor acceleration, higher fuel usage, and the check engine light. The main culprit in my case was a large vacuum leakage affecting the manifold pressure readings, rather than a faulty sensor itself. The repair included: Complete vacuum system inspection, Replacement of cracked vacuum lines, Manifold pressure sensor cleaning and testing, System pressure test verification Total cost was 235€ at my regular workshop. The car sensor readings normalized after fixing the vacuum leak, and engine performance returned to normal immediately. To provide more specific advice about your situation, could you share: Have you noticed any unusual sounds from the engine bay? Did the issues appear suddenly or gradually? Are there any other warning lights besides the check engine light? Have you had any recent maintenance work done? This information would help determine if your symptoms align exactly with what I experienced or point to a different sensor failure issue.

Last service was at 142000km and the car runs quite rough since then. After running diagnostic tests at home, I noticed irregular manifold pressure readings. The car sensor data shows fluctuating MAP values at idle, which matches the symptoms others described. Initially thought it might be a vacuum leak, but pressure testing showed no leaks. The manifold sensor connection appears clean and properly seated. Clearing the error codes temporarily fixes the issue, but problems return within a day or two. Based on the repair costs mentioned, wondering if replacing the MAP sensor first might be worth trying before more extensive diagnostics. Looking to confirm if others found sensor replacement alone solved similar symptoms.

Your situation sounds quite familiar, my T-Cross showed those exact symptoms after routine service, including the temporary fix when clearing codes. While vacuum testing came up clean like yours, I initially replaced just the MAP sensor hoping for a quick fix. Unfortunately, this didnt resolve the issue completely. What we eventually discovered was a failing electrical connection in the intake manifold wiring harness that was causing irregular MAP sensor readings. The failing connection was creating inconsistent data, leading to the symptoms you describe. The wiring issue wasnt visible during basic inspections. The actual fix required: Testing the MAP sensor circuit, Repairing damaged wiring near the intake manifold, Replacing corroded connector pins, Installing a new pressure sensor as preventive measure Total repair ended up around 380€ including parts and labor. While more expensive than just a sensor swap, it permanently resolved all symptoms including: Rough running, Power loss, Erratic MAP readings, Recurring error codes Given your identical symptoms and the fact that basic checks havent revealed obvious issues, I recommend having the wiring thoroughly tested before just replacing the car sensor itself.

Thanks for the detailed information about the wiring harness issue. That actually makes a lot of sense given my symptoms. The manifold pressure readings being inconsistent even with a clean sensor points toward an electrical problem rather than just a bad sensor. Good to know about checking the wiring connections, I had focused too much on the MAP sensor itself without considering the electrical side. The fact that clearing codes provides temporary relief also matches with what you described about intermittent wiring problems affecting engine performance. I will get the complete circuit tested rather than just replacing the automotive sensor blindly. While 380€ is more than I hoped to spend, fixing the root cause is better than wasting money on parts that wont solve the issue. Will have my mechanic inspect the wiring harness and connectors, especially around the intake manifold area where you found the problem. Really appreciate you sharing the full diagnostic process that worked in your case. This gives me a much clearer direction for addressing my ongoing sensor failure symptoms.