VW Caddy Manifold Issues: Key Symptoms & Solutions

I had a very similar issue with my 2005 VW Touran 1.9 TDI last year. Having some experience with diesel engines, I initially suspected a vacuum leak but wanted a professional diagnosis. The symptoms matched exactly what you describe, rough idle, jerking during acceleration, and reduced power output. The manifold pressure sensor was showing erratic readings, which triggered the check engine light. After inspection, the workshop confirmed the intake manifold had developed cracks due to heat scorching, causing significant air leaks. The complete repair, including parts and labor, cost 1180€. The workshop had to replace the entire manifold assembly as the damage was too extensive for repair. The job took about 6 hours. To properly diagnose your case, could you share: Exact engine code of your Caddy, Current mileage, Any previous repairs related to the air intake system, Whether you notice the problems more during cold or hot weather, If you have access to diagnostic codes from the check engine light This information would help determine if your manifold issues are similar and what specific solution might work best.

Thanks for the detailed feedback. My Caddy just hit 88657km and had its last service 2 months ago. The intake manifold problem seems nearly identical to what you described. Getting those fluctuating manifold pressure readings and engine performance issues really points to vacuum leaks. The workshop quoted 950€ for a complete manifold replacement including labor. They recommend doing it soon since the car manifold damage appears to be getting worse based on the symptoms. Does that price sound reasonable compared to what you paid? Also good to know the repair took 6 hours in your case. I will need to plan accordingly for the downtime.

That 950€ quote is actually quite reasonable for a complete manifold replacement on these VW diesels, it's about 230€ less than what I ended up paying for mine. The labor time sounds accurate too based on my experience. The key is addressing it promptly before the gasket leak causes additional problems. When my manifold pressure issues started, I initially hesitated due to the cost. That delay led to increased fuel consumption and eventually affected other components in the air intake system. Just a heads up, make sure they check the manifold pressure sensor and connections while doing the replacement. My mechanic found the wiring needed minor repairs during the job, which could have caused issues later if left unchecked. After the repair, the difference in performance was immediate, no more jerking on acceleration, check engine light cleared, and the engine ran smoothly again. The exhaust smell also disappeared completely. Based on your mileage and symptoms, you're catching this at about the same stage I did. Getting it fixed now will likely prevent more extensive repairs down the line.

The price of 950€ for replacing the intake manifold seems quite fair, especially compared to your repair cost. Your feedback helped confirm my suspicions about the vacuum leak being the root cause of my performance issues. My mechanic also mentioned checking the manifold pressure sensor during the repair, which matches your experience. The wiring inspection is definitely something I will request they include while doing the work. Given how the symptoms match, from the check engine light to the rough acceleration and exhaust smell, I feel more confident now about proceeding with the repair. The fact that you saw immediate improvement after fixing similar issues is encouraging. I will schedule the repair for next week. Better to address the gasket leak now before it leads to bigger problems. Having to plan for 6 hours of workshop time is manageable, and knowing the repair resolved all symptoms in your case makes the cost easier to accept. Thanks again for sharing your experience with such a similar manifold issue. It really helped validate both the diagnosis and repair approach the workshop suggested.