Variable intake system servomotor + Lambda faults

N

Newbers

Active member
 St Albans (one days march from London)
Z4 Coupe, E86, N52.

Just got back from independent garage who plugged in his computer after I had the engine light come on in my Coupe. Four errors :(

After clearing the codes and restarting the engine the first two returned: :cry:

2AA9 Variable Intake System Servomotor 2 Activation
2C9D O2 Sensor 2 Heating before Cat
2C3C O2 Sensor before Cat 2 not connected
2C3E O2 Seonsor before Cat 2 Internal fault.

I can cope with the Lambda (O2 sensor) and will probably change myself if I can work out which one it is (of the four up this end of the exhaust!)

Any idea what that first error might be? Valve timing?
 
Well I've been reading up and I think I'm going to have a go at the Lambda sensor first, may be that will clear the other code - if not I have to carry on looking.

I bought a copy of the BMW TIS (service manual) off ebay and it appears that there are 4 sensors. They are in pairs before and after the cats. One pair looks after cylinders 1,2,3 the other 4,5,6. As I am interpretting the codes I need to change the sensor before the cat on the 4,5,6 bank. This is not great news as it appears to be far more involved to replace - as in requires the exhaust to be removed.....
 
Just me here :D

I ordered the part from Sopers in Lincoln who seem to be competitive for forum members. I was surprised, a lambda sensor specialist - the first one that comes up on a Google search wanted £160. I found one on ebay for £111. Sopers (authorised BMW) wanted £70 + vat before a 12% discount - hurrah!

I think that the note on the TIS about needing to drop the exhaust is nonsense for my sensor. It looks tight to get to but worth a bit of a squeeze to avoid the hassle of finding ramps and dropping the 'zorst. If all else fails I have to get my 10 yo son to crawl in!
 
I'm not sure if anyone is interested but I swapped the lambda sensor this evening. If you have the BMW type tool this would be a relatively easy job (imagine a ring spanner with the ring cut to allow you to slide it over the wires the handle cut off at about 5cm with a 3/8" socket drive hole near the end). I should have got my act together and bought one of ebay for £7 but instead left it till today to realise this is what I needed. I eventually got hold of a normal Lambda sensor tool which is basically a long 22mm socket with a slit in it (to clear the wire).

Access to the sensor I needed to change (on the rear of the two manifolds) is tight so I ended up having to remove a small heat sheild this was incredibly fiddly and required buying a TX-star socket set. I don't mind buying tools they usually get used again.
Actually swaopping the sensor once I could get to it was easy. Whole job under an hour (+ about half a day chasing about to get the relevant tools :| )

My engine light is still on which I assume is due to the other fault (2AA9 Variable Intake System Servomotor 2 Activation) but I'm hoping that code was related to the faulty sensor.

I let the engine tick over for a while and got the impression that the tick over was more regular and it certainly seemed to drive OK. I think I just need to get it plugged in to a computer to delete the codes and see what comes back again.....
 
There hasn't been a lot of interest in this post but just to complete the story, I drove to Manchester and back today and just as I was about to sigh at the 50mph limit on the M1 :( when I realised that the engine light had gone off :)

I'm feeling quite smug. Specialist Cars in Luton wanted £200 to do it (not too bad) but for half that and less than an hour I bought a genuine part, the required tools and got it done without the inconvenience of getting the car to the Stealers. All very satisfying.

Feel free to PM me if years from now someone wants a hand with this same problem!
 
Newbers, thanks for this, sure it will come in handy some day. I did see your original post a while back, but couldn't help.

Unfortunately most just seem to browse the general discussion (rather than active topics) and miss these things, so please don't take offence at the lack of input... it will come up in searches when needed and the effort to plough on and update regardless is appreciated.

Good work sir :thumbsup:
 
It gives you a good feeling when it all comes together.Very good info which i hope i dont have to use. :thumbsup:
 
Should I ever need to do this, will your 10yr old be available ... Great write up, glad it all worked out. :thumbsup: :thumbsup:
 
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