All 4 injectors & NOX Sensor fail?

[rebel.ranter]

A neighbour has an e93 , 2009 with the 2.0L N46 petrol engine, 62k km on clock.
He was experiencing an occasional hesitation in 2nd & 3rd gear so He brought it to the main dealer to get a diagnosis.
They called out that the NOX sensor (oxygen sensor?) & all four injectors need replacing!
The hesitation is only when first going in to 2nd or third gear. I would have thought that a faulty sensor & all these injector issues would trigger an engine management light. Sounds like pure guess work to me, €1,600 worth of guesswork at that. Surely a faulty injector or a faulty sensor would be very coincidental, never mind all 4 failing! Also is it likely that either one could register spurious fault codes for the other?
Any ideas?

I'm gonna do my own diagnostics tomorrow for him, it just seems very odd to me.

[E46Padge]

When was it last serviced? I had a hesitation in a similar engine bmw a few weeks back. Serviced it and it was fixed.
could be bad fuel also. Some nasty stuff being sold lately. Also stay away from main dealers they prey on people and try extract as much as possible.

[Valdelisbmw]

I would say spark plugs could be dead as well ,even bmw says they should last till 100k km ,but they DONT LAST so long !! NOX sensor is not oxygen sensor !

[Ketron]

NOx = Nitrogen Oxide

Its there for environmental reasons.

Sounds highly unlikely all injectors would fail at once, failures of the nox sensor seem to be quite common on those engines though .

[TheRev]

Strong chance that one injector is gone and that, a) only available as a full set, or, b) the dealer is recommending doing them as a set - "sure while we're in there" sort of thing

[eddiem74]

I would say clear all codes Mark and see what's left or then take it for a run and see what comes back.

Dealer most likely plugged in and ran diagnostics and is addressing whatever is listed some or most of which may not be related to the issue.

NOx Sensor is used to help with emissions I had mine listed for replacement when I ran diagnostics but it had still passed NCT. Some guys seem to not bother replacing them at 400ish for the part. Supposedly over time if they are not replaced it can cause cat issues?

I replaced all my injectors recently enough due to rough idle and misfires, they were in both banks and the injectors had been upgraded so needed to do them all, no goodwill from BMW even though a known issue.

[Valdelisbmw]

have replaced by one or by two and all running fine ,coding recommended as well

[rebel.ranter]

Cheers for the replies lads. I was thinking that a first port of call was to clear the codes (if not already cleared), clear all the adaptations on DME & see how they go.

I've priced a NOX at €355 plus delivery here, I know someone who uses the site regularly:

http://www.carparts-pros.com/page_1_3.php#oeformo

Search Part number: 11 78 7 587 130

http://bmwfans.info/parts-catalog/11787587130

I'll suggest changing spark plugs as a next step after resetting the codes, it will be a cheap test to do & they need to be done anyway.

If that doesn't resolve the hesitation & the NOX error comes up I'll let him decide if he wants to try the NOX.
[hr]

have replaced by one or by two and all running fine ,coding recommended as well

Is that coding for the NOX sensor or the new injectors?

[Valdelisbmw]

Is that coding for the NOX sensor or the new injectors?

sorry ,injectors

[eddiem74]

NOx will have nothing to do with the hesitation per my limited mechanical knowledge, its purely emissions related.