[turbotel]

Following my previous posts,I am requesting advice from the community.
Here the story.

My old faithfull e90 330d had been running great,no problems.
Went in for its annual MOT ,passed ok ,emmisions ok.
Driven for a few days ,experienced loss of power ,almost stalled,driven home with reduced power.

Code P0401. registered.

Replaced egr solenoid.( making classic quacking noise )leaking vacuum.
New solenoid holding vacuum ok.
EGR starts to open at 14 ins mercury,fully open at 20 ins.
System generating 25ins+ of vacuum.( in spec)
Cylinder head coolant temp replaced(whilst intake manifold off)
Swirl flaps replaced with new blanks.
New intake manifold gaskets fitted.
Vacuum lines replaced.
Smoke tested,no vacuum leaks.
New genuine Bosch MAF fitted.

Engine runs great with MAF disconnected,smooth,power delivery linear,boosts well.no smoke,autobox changes spot on.

New maf plugged in,rough running on tickover,noisy engine,engine unblanced,
obviously un happy.
Does not adapt if left on tickver/idling.
intermittent hesitation on driving but eventually settles when up to temperature.
Throws code p0401 on next re start.
Car driven on motorway and various urban to re adapt but no success.

The egr and manifold are clear of carbon.

Everything points to faulty new MAF,but have also tried alternative MAF from MAF service Germany with no success,same end result.

My local BMW independent now has vehicle and is trying to tell me it may need a new DDE/ecu.

I am very sceptical about this diagnosis.

Is it possible that my DPF is blocking( no codes) and causing air flow probs on cold start.????
Could it be a failing (pre cat)Lambda probe.???

I am totally baffled.
Any ideas folks.?

Thanks in advance.

p.s Only codes with Maf unplugged are P0101 and P0112. NO code p0401.

[Tambohamilton]

Did you reset adaptations after installing the new maf?

[turbotel]

Many thanks for your advice.

In answer to your question.

I didnt reset adaptions because I only have INPA operational at the moment
which doesnt seem to allow me to reset maf adaptions.
Correct me if I am wrong.

I have been trying to get ISTA+ to connect to vehicle to perform this function but it will not connect despite trying everything.(another story).

I was hoping that the adaptions will self configure with driving but this just will not do the trick so it seems.

I suggested that adaptions be reset to my independent so called BMW specialist
but he said any faults will just return.
I am getting the usual feeling that he might be trying to make a meal out of this job but remain open minded at this stage.

As I mentioned the car drives excellent with (new) maf disconnected and the only faults are maf related.

The vehicle which I have owned for 3 years may have had egr issues for some time due to the failing egr solenoid(duck quack noises) but this was replaced when the inlet manifold was removed.
The egr valve and inlet manifold were very clean(probably because of lack of egr ) .
I have never had any dpf warnings /codes and suspect there is no particular problem with dpf because the car still performs excellent with maf disconnected.
Everything tells me MAF but I replaced the original with one from MAF service gmbh(good reviews)
This was unsuccesful and led me to purchase a genuine ? Bosch from Powersparks( ebay bosch approved stockist)
The codes and hologram checked out ok so unless this is a very good chinese copy I am running with the theory that this is ok.
Apologies for the long screed/answer to your reply .
Should I insist that adaptions are carried out as a starting point before going down blind alleys in order to run up the bill?

[Tambohamilton]

It's a bit beyond my knowledge, to be honest, but the factory manual says it should be done so I'd definitely start with that

[turbotel]

Update.

I am on the verge of answering my own question so it seems.

The rough running on initial startup is quickly corrected by removal of the vacuum hose to the egr valve.

No vacuum should be directed to the egr at idle (so ista+ tells me)

Why is this happening I ask myself.?.

My guess it is either a faulty(new ebay) egr solenoid valve(sits under inlet manifold) or.

Faulty ? Exhaust exhaust pressure valve situated on other side of motor with electrical connecter and pipe to DPF/cat.

Work in progress.