Scary oil leak

Today I managed to replace the seals on both the side of this pipe. It was moderately difficult DIY for me. I think this is must for all 335d and 535d owners to check their intercooler hose and replace the seals (or hose if hose is split) because so many of these bi-turbo engine suffer from leaky hose problem. It should have been a recall ideally. Here is the link for the DIY I have posted. All you need is a ramp so that you can reach the pipe from under the car and most tricky bit is to remove the top (turbo connection) end of the hose which took most of the time for me, otherwise it was all simple.

Drove the car for appx. 10 miles after finishing DIY and it 'seemed' turbo lag isn't there anymore; or atleast has reduced quite a lot. I can't confirm this 100% yet as it could be just in my mind; I will drive it for some more time and then report back. No oil leaking yet but it is too soon to conclude.

If this leak continues there isn't any option left but to change the whole pipe, there is no way any other (aftermarket or silicone) pipe will fit replacing this one unless heavily modded which IMO isn't worth it because of too much work involed. Biggest problem is reaching those hose end, intercooler side is easily reachable from underside but top end is bit difficult but still doable that too only from underside. Not worth doing if you haven't got a ramp.

Btw. gave a visit to halfords today and saw a lifting kit for £45, not a bad deal considering just the ramp doesn't come less then £20-25 on its own. I am not sure on the quality though. I didn't use this as I had a ramp but if I didn't I would bought this.

Spoke to my dealership today to findout what parts where replaced under warranty when I reported turbo boost problem last year and they happily gave these two parts numbers:

11.74.7.797.129 and 11.65.7.796.857, basically item number 10 and 15 from the picture below

I am not sure where these pipes are located and whats condition of those ones, as far as I could see it was just the big red pipe (part number as given by Sporty1 above, big thanks for that mate) which is leaking.

I spoke to an independent BMW specialist called Phil from CPCPE and he told me that oil leak from the red pipe and so much lack of turbo boost at low rev may not be related. He continued saying this is very common issue with x35d twin turbo engines where a few blocked pipes can cause the low rev power loss. He quoted me £300 (parts and labour, parts he said is just around £20) to get a few turbo related hoses replaced. Phil said he has seen this problem before and fixed it this way. Regarding oil leak he said it is normal but without seeing it he can't say anything. A split or badly damaged red pipe, he said will cause total powerloss (you car won't go above 60 or so) and there won't be any performance at all. He reckons that your small turbo would be fine (big relief) and little bit of wetness near red pipe is normal.

I will get it fixed whichever way in next two weeks hopefully.

Sporty1 wrote: ETA County court route??? For what? You need to give them the opportunity to fix the car, you cannot just take it somewhere else and then issue court porceedings. You will lose.

Exactly. You have to give them a reasonable chance to fix the car before you have any grounds to complain.

As Sporty says, agree to pay for the diagnosis if they find the problem is not connected to the part they replaced under warranty.

Another route of information might be to BMW UK to find out their view on who should pay for the diagnosis in the event that the fault is with a bit replaced under warranty?

If they say anything other than the dealer then sell the car and move to another marque