T-Roc MAP Sensor Issues Causing Performance Drop

After experiencing similar symptoms on my 2018 VW Tiguan 2.0 TSI, I found the manifold pressure sensor issue was actually pointing to a larger vacuum leak problem. The sluggish performance and increased fuel consumption matched exactly what you describe. The sensor failure triggered the check engine light, but replacing just the MAP sensor would not have solved the root cause. A proper diagnosis revealed deteriorated vacuum lines near the intake manifold. The rubber had developed small cracks, causing false manifold pressure readings and affecting engine performance significantly. The complete repair required: Full vacuum system inspection, Replacement of damaged vacuum lines, MAP sensor replacement, System pressure testing, ECU reset This was a serious issue that needed immediate attention, as continuing to drive with vacuum leaks can lead to further engine damage. The faulty sensor readings were causing the engine to run rich, explaining the high fuel consumption. Recommend getting a proper diagnostic scan first, then having a thorough vacuum system inspection before jumping straight to sensor replacement. The symptoms point to a potentially larger issue that needs professional evaluation.

Thanks for the detailed reply about the vacuum system and manifold pressure issues. This really helps, as the symptoms match exactly what I am experiencing with my T-Roc. Do you remember roughly how much you paid for the complete fix? Also, has everything been running smoothly since the repair, or have you noticed any other issues? Want to make sure I budget correctly and know what to expect after the sensor replacement and vacuum line work. Since the MAP sensor is still giving me grief, I might go ahead with your suggested approach, getting a full diagnosis first before replacing parts out of nowhere. Makes total sense to check the entire system rather than just trusting the initial sensor failure indication.

Great to report back that since having the repair done, my Tiguan has been running perfectly. The complete fix resolved all performance issues and the fuel consumption returned to normal levels immediately after addressing the vacuum leakage and faulty manifold pressure sensor. The total cost came to 235€ for the full repair, which covered fixing the large vacuum leakage that was causing the manifold sensor to read incorrectly. This price included the diagnostic work, parts, and labor. Looking back, it was money well spent considering how much extra fuel I was burning before the fix. The mechanics found the vacuum leak was actually quite significant, which explained why the manifold pressure readings were so far off. Since the repair six months ago, the engine response is crisp again and the check engine light has stayed off. No other issues have emerged related to the pressure sensor or vacuum system. Your approach to get a complete diagnosis first is definitely the right way to go. The manifold sensor readings can be thrown off by various vacuum system issues, so targeting the root cause rather than just swapping parts will save money in the long run.

I took my car to a reliable shop yesterday after reading the helpful advice here. The diagnostic scan confirmed both a vacuum leak and MAP sensor issues, matching exactly what was suggested. The mechanic found cracked vacuum lines near the intake manifold, explaining the poor engine performance and high fuel consumption. Total repair cost came to 290€ including: Complete vacuum system repair, New MAP sensor installation, Labor and diagnostic fees Already noticed a huge improvement in engine response during my drive home. The sluggish acceleration is gone and the check engine light cleared after the repair. The mechanic explained how the manifold pressure sensor was reading incorrectly due to the vacuum leaks, which caused the engine to run rich. Really glad I got the full system check instead of just replacing the sensor. The repair cost more than initially expected, but fixing the root cause should prevent future issues. Will update if any problems return, but so far the car feels like new again.