Hey guys. I've been investigating smoke behind the engine area which was down to a loose clamp when I noticed this pipe. The left side pipe on the diff pressure senssor connects to pre-DPF. The second pipe runs to the side of the timing belt cover and I assume it has to connect to the post DPF pressure connector. As far as I can see, there doesn't appear to be anything broken on the DPF or anywhere for this to connect to. DPF is working (AFAIK) and car regens as normal. I've never noticed the DPF light come on the dash and use VAG DPF to monitor as and when a regen is required.

 

Is it normal for this pipe to be connected to nothing? Other posts indicate the post DPF usually measures atmospheric pressure but surely this didn't roll off the production line like this unless the previous owner had a wrong DPF fitted?

 

Anyone ❓

Its normal, the word "differential" is the clue, it compares the DPF pressure with atmospheric pressure & the tube is to sample the atmospheric pressure, there will be some reason why they dont just have an opening on the sensor, I dont know the reason for that but the open tube is normal.