VW Transporter: Engine Light & Power Loss Mystery Fixed

Dealt with a similar situation on my 2003 VW Touran last year. Have some basic experience with car maintenance but nothing too advanced. The symptoms you describe match what I experienced, poor acceleration, increased fuel consumption, and sluggish engine response. After checking with my workshop, they identified a large vacuum leakage affecting the MAP sensor readings. The intake manifold had developed small cracks causing incorrect sensor data. The total repair came to 235€, which included: Diagnostic testing, MAP sensor replacement, Fixing the vacuum leak, Labor costs The repair took about 3 hours and solved the issues completely. Fuel economy returned to normal and the engine response improved significantly. Before suggesting more specific solutions, could you provide: Engine size and type, Current mileage, Any recent maintenance work, Whether you notice any unusual sounds, If the check engine light shows any specific error codes This information would help determine if your issue matches what I encountered or if it might be something different with the sensor system. The workshop mentioned sensor failure can often be related to vacuum leaks in the intake manifold system, which is worth investigating before simply replacing parts.

Last service was done at 112126km and they found nothing unusual. The symptoms match what you described perfectly, especially the poor engine performance and fuel consumption issues. Tested with an OBD reader and got error code P0106 which confirms the manifold pressure sensor problem. What concerns me is that the automotive sensor was already replaced about 25000km ago. Could there be an underlying issue causing premature sensor failure? The engine runs rough especially during initial acceleration. Would appreciate advice on whether I should look for vacuum leaks before replacing the pressure sensor again. Not keen on paying for another sensor if it will fail quickly.

Thanks for providing those details about the P0106 code and previous sensor replacement. Having gone through this myself, a second MAP sensor failure in just 25000km definitely suggests an underlying issue. In my case with the Touran, the workshop initially just replaced the sensor, but it failed again within 6 months. The real problem turned out to be a deteriorating intake manifold gasket that was allowing unmetered air into the system, leading to incorrect MAP sensor readings and eventual sensor failure. Key points from my experience: A thorough vacuum leak test is essential, Check all intake manifold mounting bolts for proper torque, Inspect the intake manifold gasket for deterioration, Test the wiring harness connected to the sensor for damage The complete fix for my car involved: Vacuum leak testing (45€), New intake manifold gasket (85€), Replacement MAP sensor (150€), Labor (180€) Total repair cost was higher at 460€, but the fix has lasted over 2 years now with no sensor issues. The manifold pressure readings have remained stable and fuel consumption returned to normal. Would strongly recommend having the intake system thoroughly checked for leaks before simply replacing the car sensors again. A smoke test can reveal vacuum leaks that might not be obvious during visual inspection.

Having compared notes with a fellow VW owner and considered the advice, I think I need to investigate this more thoroughly. The P0106 error code and previous sensor replacement history really point to a bigger issue hiding underneath. Good to know the workshop discovered similar vacuum leak problems in your case. At 235€ for your initial repair versus 460€ for the complete fix including gasket replacement, spending more upfront to address potential intake manifold issues makes sense rather than repeatedly replacing sensors. Going to book the car in for a proper vacuum leak test first. The fact that my manifold pressure sensor failed after only 25000km when they typically last much longer definitely suggests underlying problems with the intake system. Will make sure they check the manifold gasket and mounting bolts thoroughly. Will update once I get the test results. Hoping it turns out to be something straightforward like a deteriorated gasket rather than more serious engine issues. Really appreciate you sharing your repair experience, helped me understand what to look for beyond just sensor replacement.