Sean H
Member
- Joined
- Sep 8, 2023
- Messages
- 13
- Reaction score
- 10
I've learned a lot from this forum, as well as working my way through various faults on my '08 D40 auto. I would like to share some solutions, which I tried before eventually finding a root cause. It all began with a recurring DPF blockage. I removed the offending material from the pipe and fitted some recalibrated sensors. I was able to restart to car, but it blew a lot of black smoke. I cleaned the injectors with Liqui Moly. Certainly smoother on acceleration, less rattle, but still down on power and blowing smoke. To rule out intake problems, I washed out the intercooler and cleaned the intake tract. (The EGR is not a factor). Still blowing smoke. I had previously replaced the boost control solenoid, but that had not improved my power. While I was in there I replaced all the vacuum hoses with silicon tube. Alas it was still smoky and doughy. I then realised that there is a small connector hose from vacuum source to the small manifold. It was badly perished. After replacing this, the car went like a rocket and the black smoke is barely noticeable. There are certainly many possible causes for the black smoke problem, or lack of boost. However, after this experience I would recommend ensuring your vacuum source is sufficient before proceeding with other remedies.
