Lambda sensor.

[Corkery11]

My engine management light has been coming on over the last few months, I have therefore decided to give in and swap lambda sensors following advice in a previous thread. However now I have removed the undertrays I can see a sensor before the catalyst and one after the catalyst, which one should I be removing?
Ta Mark.

[NathanK]

I had flexy pipe replaced, which required the bit next to the engine to come off as well. Don't know its technical name, but its the 4 to 1 bit. My mechnanic said the sensor in that is the the lamda sensor. Also you will knacker it taking it out apprarently, so need a replacement sensor on hand.

I have an S1 and I think that was the only sensor in the exhaust. Could be wrong, I look at a monitor all day so what do I know

[tuscan_thunder]

Corkery11 said:

My engine management light has been coming on over the last few months, I have therefore decided to give in and swap lambda sensors following advice in a previous thread. However now I have removed the undertrays I can see a sensor before the catalyst and one after the catalyst, which one should I be removing? Ta Mark.

check the exhaust for leaks first in case that's having an effect.

The lambda is in the manifold (I believe) nearest the engine. It will quite probably break coming out. Expect to have to drill it out or at least use a lot of heat to get it out. You may also have to fabricate a threaded collar for the new one to sit in as the threads will probably strip when you take out the old one. It's not a fun job. It should be very easy but, as ever, it isn't.

[Corkery11]

Hi thanks for the replies.
Had a lucky break as the sensor after the Cat was seized solid, whereas the sensor after the Cat came out comparitavely easily. Popped in a new sensor and started up the car and was chuffed to see no engine management light. Turned off the engine and refitted the undertrays. Of course once I'd done all that and went to move the car of the ramps the effin light came back on. It seemed to have a hunting tickover initially but that appears to have setled down after a 20 minute drive.
Please tell me that if I ignore the MIL light, the mysterious Black Boxes will somehow realise where the problem is and all will be well (I may have read somewhere about the Engine management re-learning parameters or something). Or, if you know better, where do I need to point my spanners?

[tuscan_thunder]

I'm not sure if resetting the ECU would work? I don't know how this works on the K, but on most cars, you just disconnect the battery and leave it, say overnight.

[cej]

you shouldn't have to leave it disconnected for that long. A couple of minutes is enough

[GTRene]

yep, just disconect one pole(earth is fine) for a few minutes then in one!! move replace it...so replace the pole in one move, otherwise to many sparks and conects are not making the ecu happy
GTRene

[Corkery11]

Just tried diconnecting the earth from the battery but it does not seem to have made any difference. Any other ideas very welcome especially if they appear to be in the same price bracket as the previous ones. Keep em coming.
Thanks again.

[GTRene]

Then you better read this complete story to understand how it can work...maybe you find a sollution in this story...you also will find out that that MIL light have many more sensors on and around the engine...

www.pistonheads.com/gassing/topic.asp?h=0&f=15&t=259989

GTRene

>> Edited by GTRene on Friday 14th April 17:38

[Corkery11]

Thanks for all the info. on the link you sent. It looks like a trip to a dealer may be imminent, so I'd best dust down the credit card.

[GTRene]

yep could be, some little "easy" things you sometimes can find yourself, like some loose wires on sensors or coroded clips that are conecting those sensors...or sometimes 3 or 4 times starting the engine/contact? will reset the MIL when there only was a small hickup, otherwise they have to connect the car to a computer to find it out...better ask the price first...? that way no furter surprises.
good luck
GTRene