E91 Straight Six Bearding

[g3org3y]

Thanks for the info JakeT. I did the DISA on my E46...didn't realise it was an N52 concern as well.

[helix402]

ferrisbueller said:

Definitely be interested in knowing who the OEM supplier is. Autodoc shows a few options.

I don’t know who makes them for BMW for the N52 but Pierburg often make this type of part.

[Swervin_Mervin]

I've never checked mine. Now wondering if I want to or whether to live in blissful ignorance

[stevesingo]

JakeT said:

I've been chasing a low engine speed stumble/hesitation when going at the throttle quickly since I've had the car. It was always worst when coming out of the Peage fast lanes in France, picking up from low revs in third.

I had a similar issue last year. Normally 1600-1800rpm, coming on to the throttle. Turned out to be the VANOS valves. I removed them, cleaned and replaced in opposite sides, and removed and cleaned the oil supply check valves. Both were pretty clean anyway but this cured it for a week or so but then it came back. I then did a INPA check where you can manually target a cam angle. They were really sluggish in response, taking 1-2 secs to hit the target.

Fitted two new valves and all was good. Rechecking the response times on INPA showed a marked improvement.

[JakeT]

stevesingo said:

I had a similar issue last year. Normally 1600-1800rpm, coming on to the throttle. Turned out to be the VANOS valves. I removed them, cleaned and replaced in opposite sides, and removed and cleaned the oil supply check valves. Both were pretty clean anyway but this cured it for a week or so but then it came back. I then did a INPA check where you can manually target a cam angle. They were really sluggish in response, taking 1-2 secs to hit the target.

Fitted two new valves and all was good. Rechecking the response times on INPA showed a marked improvement.

I cleaned and swapped mine too, and it seemed to do the same. I might do the same targeting a cam angle in INPA. DISA valves can also be actuated through INPA.


For the OEM supplier, the one I took off and replaced were both MAHLE valves.

[ferrisbueller]

Swervin_Mervin said:

I've never checked mine. Now wondering if I want to or whether to live in blissful ignorance

Me too! Suspect removing the inlet manifold would necessitate swapping CCV pipes, too, as they appear to fail as soon as you look at them.

I think:

DISA Outer 7579114
DISA Inner 7560538

Frail CCV Pipe 7522931, circa £60

[JakeT]

I did my CCV system as I was swapping the starter and it was a very sad affair. The hose that runs from the valve under the inlet down to the sump is the worst. It takes a LOAD of pressing to get it on, and I'm not sure it's completely on. Getting the top connection onto the valve is just as difficult too, as there is no room to put your hands in there. I decided to change those bits namely so I don't need to go back in there for some time, but boy it was a miserable couple of days. My starter motor was the main reason for all of this work though, as it was on the way out.

[ferrisbueller]

Guessing you bought a kit similar to this?

https://www.autodoc.co.uk/vaico/8102554

Edited by ferrisbueller on Wednesday 18th November 14:01

[JakeT]

I bought a Febi Bilstein kit from C3 BMW comprising of the valve, and all three hoses.

I also bought a Denso starter, and the one that came out of mine was a Denso part with a BMW label on it. In addition to that, I bought a set of Inlet manifold gaskets, a throttle body gasket, and the new ali bolts that affix the starter.

[MajorMantra]

g3org3y said:

Thanks for the info JakeT. I did the DISA on my E46...didn't realise it was an N52 concern as well.

Same, possibly even the first time this has been mentioned on the thread?

[croissant]

JakeT said:

A friendly reminder for owners of the petrol variety (namely N52) owners to have a check of those DISA valves.

I replaced the starter and CCV system in mine over the past couple of days, and found...

.....

Followed by the flap and pin inside the inlet. Fortunate it didn't cause any real damage. I checked the smaller one, and that was fine. A new one from BMW is £260, though.

That's interesting. I have a 330i N52 and it has an occasional stutter in high gears at low rpm. I've just learned to keep the revs up when driving and don't experience it.

I've always suspected something might be up with the disa. Is it difficult to remove and have you noticed any improvement since changing to a good one?

[bmwmike]

Any six pot petrol owners had to repair their CCV or replace the cam cover (ccv integrated)? just curious if you had success with hacking it open and replacing the diaphragm vs. whole cover. My n53 needs doing, weighing options at moment. Hack is my first choice to avoid fiddling with injectors etc.

[JakeT]

croissant said:

That's interesting. I have a 330i N52 and it has an occasional stutter in high gears at low rpm. I've just learned to keep the revs up when driving and don't experience it.

I've always suspected something might be up with the disa. Is it difficult to remove and have you noticed any improvement since changing to a good one?

I drove around it too. But sometimes it catches me out if I'm lazy with the gears.

It's not a mega job to check the large one. The inlet bits need to come off, and a bracket that holds a wiring bundle in my case. You might be able to get away without removing some bits though.

Mine's a silver top N52, so no help there, Mike. I think the N53 valve cover can come off without removing the injectors, though. You can get a new diaphragm though, I'd replace that first. Someone on here had a russian kit that works fine, and they said it cured an oil consumption issue they had. Is yours using some oil now?

[bmwmike]

JakeT said:

I drove around it too. But sometimes it catches me out if I'm lazy with the gears.

It's not a mega job to check the large one. The inlet bits need to come off, and a bracket that holds a wiring bundle in my case. You might be able to get away without removing some bits though.

Mine's a silver top N52, so no help there, Mike. I think the N53 valve cover can come off without removing the injectors, though. You can get a new diaphragm though, I'd replace that first. Someone on here had a russian kit that works fine, and they said it cured an oil consumption issue they had. Is yours using some oil now?

No, not using oil at all - as far as I can tell. I've only done 2000 miles in the past 12 months though. It has started squealing, and there is extra vacuum than usual at the oil filler cap (not huge amount mind, can still lift the lid off easily) and the noise stops when the oil filler cap is lifted. Pretty sure its CCV. May try the russian approach first as its "easiest". Only 70k too, bit annoying, but ho hum - probably stupidly short once per week shopping trips for the past 6 months, only couple of miles each way. Never gets fully hot.

[stevesingo]

JakeT said:

croissant said:

That's interesting. I have a 330i N52 and it has an occasional stutter in high gears at low rpm. I've just learned to keep the revs up when driving and don't experience it.

I've always suspected something might be up with the disa. Is it difficult to remove and have you noticed any improvement since changing to a good one?

I drove around it too. But sometimes it catches me out if I'm lazy with the gears.

It's not a mega job to check the large one. The inlet bits need to come off, and a bracket that holds a wiring bundle in my case. You might be able to get away without removing some bits though.

Mine's a silver top N52, so no help there, Mike. I think the N53 valve cover can come off without removing the injectors, though. You can get a new diaphragm though, I'd replace that first. Someone on here had a russian kit that works fine, and they said it cured an oil consumption issue they had. Is yours using some oil now?

Honestly, I don't think any stutter at part throttle is related to DISA issues as if a valve is inactive, stuck open or close, or missing (effectively open), then the symptom you would expect is lower torque in the rev range where the valve should be operating such as;

Small valve stuck open = reduced torque at low engine speed
Small valve stuck closed = reduced torque in mid range

Large valve stuck open = reduced torque in mid range
Large valve stuck closed = reduced torque at high rpm

Both Stuck open = Reduced torque low and mid rpm
Both Stuck closed = Reduced torque mid and high rpm

I have had a sticky large valve in the past and the car was flat at the top end. Sometimes it would open later than programmed and instead of a progressive increase in torque as the rpm passes 4500rpm, there was a pronounced jump at 6000rpm.

IME hesitation at low rpm, part throttle is VANOS issues where the cam position lags behind target. WHen the engine is on cat warm up during the first 90sec of so immediately after cold start, the issue doesn't show as the exhaust cam position is set to aid cat warm up.

[Swervin_Mervin]

Whereas ime hesitation/stutter at low rpm under load was down to the DME having a bath

Never suffered any since that was sorted

I now seem to have an exhaust leak though. Cold starts (plus lack of use at present) and it's stinking in the cabin. Best get it looked at along with the MOT that's due

ETA - Actually after a bit of reading I'm wondering if it's the valve cover gasket that needs doing. Anyone else had this issue? It's only on cold starts - once up to temp there's no smells at all, so that suggests it's not an exhaust leak.

Edited by Swervin_Mervin on Friday 20th November 14:28

[beambeam1]

Swervin_Mervin said:

ETA - Actually after a bit of reading I'm wondering if it's the valve cover gasket that needs doing. Anyone else had this issue? It's only on cold starts - once up to temp there's no smells at all, so that suggests it's not an exhaust leak.

Hmm, think I may be getting the same so would be interested in what replies you receive.

[paulguitar]

Evening all. I realize this is not a shooting brake, but are coupe owners allowed to join in here? I will be getting this a week from tomorrow, N53 330i SE:

[g3org3y]

V nice, congrats. I've always thought the Coupe better suited the non sport look. (unlike the saloon and Touring which really benefit from the M Sport kit)

[ferrisbueller]

paulguitar said:

Evening all. I realize this is not a shooting brake, but are coupe owners allowed to join in here? I will be getting this a week from tomorrow, N53 330i SE:

I recognise that, primarily due to the wheels. Can't think where I saw it, was it an ebay purchase?