Lambda/o2 sensor questions?

[Spendyrx]

Just a few quick questions:
Just picked up a 1.1 106, it's been sat since June 2013, fair play though she started first time... This is where my problem lies.

1) mot fail
Fast idle - lamda fail @ 1.580 (max limit 1.030 (passed hc and co)
Second fast idle - hc fail @ 204 (max limit 200)
Lambda fail @ 1.305 (max limit 1.030)
Natural idle - passed

I'm going to check the sensors with live data the weekend and hopefully I'll get an answer but that leads me on to the next question.

2) the mot inspector asked if the car had been sat idle, does this mean I can clean up the lambda sensor with carb cleaner or just blast crap off it with a good run?

3) it's not that really a necessary question but why 2 lambda sensors? I'm still learning :zainy:

[Chipwizards]

There's either an air leak in your exhaust which is diluting the gasses causing a high lambda or the test probe wasn't far enough up the exhaust tailpipe.
An engine absolutely will not run leaner than 1.3 at best and most engines struggle above 1.1.
If it even was running 1.3 in your second test the HC's would have been much higher because HCs increase as you go leaner from lambda 1.0.
I would wager there's nothing wrong with the lambdas but the cat probably needs getting hot to bring its efficiency up.
If it fails lambda again 'mask' the exhaust tailpipe with a rag and see what happens.

[Spendyrx]

Haha, funny you say that, I knew the exahaust was blowing a bit before it went in which made me think I'd have on my mot sheet 'major leak of exhaust gasses fail' but there wasn't! There was because I found out last night when I had a good look the exhaust clamp wasn't tight lol, I did tighten I'd properly but it's slightly leaking out of the sides so tomorrow I'll whip it off and paste it up for mot next week.

If you're wondering why didn't I just fix it before putting it in,
I bought the car a fortnight ago and done a check myself and then wanted to mot it before I spent money on it (like I usually do with cars) before an mot only for it to come back with 10 times more work or work valve seals or masses of rust! Fair play though, it came back with less work than I originally wrote down!

Rear passenger wheel cylinder seized, emission fail and exhaust mounts and 2 front tyres. Advisory for the vertical play in beam (trailing/swing arm bearing on passenger side) not bad for 80 quid I'm my book! And she's rust free too :D

Thanks for the reply.

[axsaxoman]

nice explanation wayne --proper job

[Spendyrx]

Just done obd live data test -
O2s 11 reads 0.000v
02s 11 reads 0.000v at idle and fast idle at 2000 rpm
Does this mean dead sensors? I'm guessing it is!!!!

I have shrtft 11 and 12 that are read in %
11 fluctuates up to 2% at idle
11 is stuck on 99.21%
Any thoughts on this? Cheers

[Spendyrx]

Forget that, just tested it on my other 106 and had exactly the same readings, no eml saying about lambda!
Do have a fuel trim bank 1 code but the head gaskets failed and I think it's been picked up from there along with multiple cylinder missfire and undefined!

[Spendyrx]

Thanks for all replies, passed mot today.
I fixed the leaky exhaust, put redex and super in and it done the job. Whether it was just down to the fact that I fixed the leak I'm not sure but put redex and super in just to be safe :)