Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Breather valve?

Perhaps the engine was not designed to just burn fuel at idle for extended periods to simply warm it up during a lay up Use it throughout the year by driving as it was intended even if this means waiting a month in my case for a gap in weather/salted roads given the awful winter we are having this year.

If the problem exists when driving the car regularly then consider the PCV kit. Gen2 B58 engines use hybrid direct and manifold injection so may not be as vulnerable to carbon build up on valve stems as earlier pure direct ones.

Richard, totally agree. Taking it off the road for the winter might prove to be a poor decision. We live and learn.

Apologies if already mentioned. I think I read in the handbook, BMW don't want you to leave the engine idling for extended periods. They've programmed a cut-out on B58s after the engine has been sat idling for too long [I think it's set at 5 minutes]. Maybe that's what you are experiencing?

"direct and manifold injection so may not be as vulnerable to carbon build up on valve stems as earlier pure direct ones."

Yes this is quite possibly correct. However BMW techies say they still sometimes have to remove inlets on B58s and blast clean with ground walnut shells on high mileage examples or cars used mainly for short journeys. It is not an insignificant job.

When I removed the head of my 2014 Plus 4 GDI engine after 20 k Miles which had been on VTA (vent to atmosphere) from new the inlet tracts and inlet valves were almost like new. The GDTI (260 bhp Focus ST turbo engine) I replaced it with

has also beneffitted from VTA from new.

pip pip

Could be Mart, and that was one of my theories when I had the (similar) issue last year,

My understanding is that this is when the car is idling in Park, and is implemented by BMW for emissions.

I’m not convinced that MMC have implemented it, but I try to keep the car out of Park as long as possible, and it doesn’t really explain why, after the first stall, and subsequent ignition off, ignition on, start engine sequence the next stall is often within the first minute, nor why it happens when the engine is held at higher revs. And. of course, the engine was fine running much longer at the beginning of December.

It’s due to go back to the factory on the 9th, then we’ll know for sure (hopefully). It’s not something I want to test out on the roads!

Thanks cooper man.

John I just mounted the catch can on the bulkhead, all engine derivatives require you to find an optimum place then redirect the crankcase breather to the in side of the catch can. I then repiped the inlet side from the out side of the catch can to the inlet connection. you need a sealed catch can with just an in and an out side.... not the type with a filter on top as you will loose the vacuum pull.

Thanks cooper man.

John I just mounted the catch can on the bulkhead, all engine derivatives require you to find an optimum place then redirect the crankcase breather to the in side of the catch can. I then repiped the inlet side from the out side of the catch can to the inlet connection. you need a sealed catch can with just an in and an out side.... not the type with a filter on top as you will loose the vacuum pull.

John, Forgot to add, I've ran BMW cars since the 1970's up until my last one which I sold in 2017. Never had any issues with their direct injection cars so I don't think you'll need to install one on your new plus 4!

OK. The internet suggests after 100k so I'll pass on that

Well on the power to weight ratio of the CX plus four the actual load on the engine is going to be way less so a well serviced engine probably won't have the wear issues associated with the heavier cars and might never need one fitting. Just as an aside here, I have never found modern engined cars to vaporise much oil contaminant through the rocker box breather, certainly not enough to warrant a catch can install either as a separate item or duel model in conjunction with the crankcase can.

Cooperman is spot on with his proof of just how clean the intake side will stay if you vented to atmosphere and you can achieve this using a filtered can however be aware of a potential MOT failure as this is not technically allowed but there is always the simple reversal method for that time of year. Lexus were the first to go with direct and indirect injection working together and this system certainly keeps the intake side nice and clean... as yet I haven't looked at the BMW engine to see if this is the case with it.