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Maniac wrote: ↑Wed Jan 10, 2018 6:38 pm They don’t accept it’s their doing. Looking online this seems to be another N54 weakness. It just happens due to a design fault. Likely missed or unseen by many that have it

https://www.pistonheads.com/gassing/top ... 0&i=999999

It’s not resolved the poor cold running. Waiting on the PCV pipe as the next test now.

you'll find out soon enough! it will either run better or not. probably the pipe all along!

So it went in yesterday for the replacement pipe (crankcase vent/emissions control).

It ran fine on the way there just like old times which was v odd.

They’ve replaced the pipe and I’ve just taken it from a stone cold start run. It was normal just like yesterday.

So at this point I don’t know whether the pipe has sorted it or it’s just a fluke.

Maniac wrote: ↑Sat Jan 27, 2018 3:51 pm So it went in yesterday for the replacement pipe (crankcase vent/emissions control).

It ran fine on the way there just like old times which was v odd.

They’ve replaced the pipe and I’ve just taken it from a stone cold start run. It was normal just like yesterday.

So at this point I don’t know whether the pipe has sorted it or it’s just a fluke.

Bugger

Third day and 2nd cold start ran as normal so it’s looking good. No drop off power or particularly weird gear changes. Fingers crossed.

So it’s been stood unused for a few days and today’s first cold start saw some slight hesitation before gear changes which quickly reduced as the car warmed up. There’s no loss of power during or after changes as there was before. In fact it’s more responsive than it’s been in years.

So now it’s left me wondering if it was always a bit sluggish/you could feel the gear changes when it was cold and I’m focusing on something that’s as it should be.

Maniac wrote: ↑Tue Jan 30, 2018 6:04 pm So it’s been stood unused for a few days and today’s first cold start saw some slight hesitation before gear changes which quickly reduced as the car warmed up. There’s no loss of power during or after changes as there was before. In fact it’s more responsive than it’s been in years.

So now it’s left me wondering if it was always a bit sluggish/you could feel the gear changes when it was cold and I’m focusing on something that’s as it should be.

looking a gift horse in the mouth?

Possibly. Sensitivity on the throttle is hugely improved, I can’t remember it being so instant. I suspect the pipe or valve cover has been an issue for a long time, finished off or shown up by the injector replacement works.

Dario, do me a favour tho would you. When you use the Z next, see if you can feel the gear changes when setting off with a stone cold car. If you can and they smooth out to imperceptible when warmed up, then what I’m seeing there is normal.

I always felt I could never feel the changes whether warm or cold but perhaps I’m just mistaken.

The sensation I’m getting from cold start is as if it lifts off the throttle just a bit before the shift up.

Maniac wrote: ↑Tue Jan 30, 2018 6:26 pm Possibly. Sensitivity on the throttle is hugely improved, I can’t remember it being so instant. I suspect the pipe or valve cover has been an issue for a long time, finished off or shown up by the injector replacement works.

Dario, do me a favour tho would you. When you use the Z next, see if you can feel the gear changes when setting off with a stone cold car. If you can and they smooth out to imperceptible when warmed up, then what I’m seeing there is normal.

I always felt I could never feel the changes whether warm or cold but perhaps I’m just mistaken.

The sensation I’m getting from cold start is as if it lifts off the throttle just a bit before the shift up.

I was out in it this morning in cold conditions and the clutch/gear thing is pretty much as described. worst bit when cold is coming in to a junction or a roundabout, sometimes it likes to select too low a gear like first when second would have been the better bet. clutch changes can be felt when cold, but warm is another thing entirely, like seamless gearbox.

thats the problem with stuff like this, paranoia is a difficult thing to disengage from when trying to be objective lol

Good to know. Then I guess we’re all good and it was the vacuum leak that caused the power loss issues.

Maniac wrote: ↑Fri Sep 15, 2017 6:56 pm Sigh, the rough when cold running has returned. The longer the car stands the rougher it's next start. Still no codes though, don't want to risk diagnostic fees until it's showing codes.

It's not a regular misfire, it's spotty. It's also bouncing revs when I try and hold them other than at idle.

but surely, they still haven't fixed the original problem have they?

Yes. Original issue was misfire. That was resolved by new injectors.

When returned I had no misfire but a weird power loss around shifts, it felt like it would stall when slowing / shifting down and felt like someone hit the brakes when shifting up.

That’s been resolved by the new valve cover and PCV pipe.

SO whatever caused the improvement was short lived. We’re back to the power loss before shifting up again on cold starts.

This is really starting to annoy me now.

Maniac wrote: ↑Sat Feb 10, 2018 4:21 pm SO whatever caused the improvement was short lived. We’re back to the power loss before shifting up again on cold starts.

This is really starting to annoy me now.

You could have a smoke test to check for any further potential air leaks if it hasn’t been done already.
The symptoms you describe are very similar to the ones displayed by Ann’s mini, that was a faulty vanos solenoid causing hesitation on gearchanges & an imprecise “fluffy” feel on reapplication of throttle or pulling away from standstill, that never triggered an eml either.
Rob

THats the thing, it could be lots of things and thedealer doesn’t seem to Be able to sense it mainly as it has to be stood overnight and the issue lasts just the first few minutes of driving.

Took it out for a proper WOT traction fest of some damp back roads today and it didn’t miss a beat. I half hoped something would cause an EML but I’m not that lucky.

So I’m still not happy with how it’s running. Back to the dealers for 3 days and they don’t see anything wrong but then they have no reference point as to how it should be. They reset the DCT in case that was the issue which has resulted in a very sharp initial bite on set off or hills.

Two things I have discovered, a recent cold start at ambient 13C was much better than one this morning at 1C. Also 99 Ron fuel improves the situation over 95 Ron.

To me this goes right back to the injectors again, either faulty or wrongly configured.

I’m waiting on a response from the mechanic that worked on it most recently and then I’m going to insist they double check the injectors and coding configuration.