Lambda sensor

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CJ B
Posts: 366
Joined: Wed Dec 15, 2004 1:15 pm
Location: Northwich (not Norwich)

Lambda sensor

Post by CJ B »

Hi, I had to make a long journey on Christmas day and checked my oil, WHAT A NIGHTMARE the bloody dipstick would not go back in. Eventually after much tweeking of the angle of 'bend in the end' I just managed to get the bu88er back in.
It was at this point I noticed the wire to the lambda sensor was broken which I thought I must of done struggling with the dipstick so I bodged it back together swore another dozen times or so (taking the total to about 1500 F**K's - not bad for a Christmas morning) and set off on my journey.
The car was lumpy at low revs and idled a lot higher than before (it does settle down) , I thought the wire must of come off again but it was running and I had to be on my way so I left it to fix another day.
I just checked and the thing is still connected!
Does the car run better without the lambda sensor or is it just coincedence?
I have no idea whether the cat has been gutted.
Could resetting my ECU sort this out?

Thanks for your help,
Chris.
^Trickster^
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Re: Lambda sensor

Post by ^Trickster^ »

You need the lambda sensor for correct operation of the engine.

Graeme
PW@Woodsport
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Re: Lambda sensor

Post by PW@Woodsport »

do a fault code pull to find out if the sensor is working,my guess is you have pulled the wiring out of the sensor and its now fubarred.As graeme says its essential for the engine to run properly.
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CJ B
Posts: 366
Joined: Wed Dec 15, 2004 1:15 pm
Location: Northwich (not Norwich)

Re: Lambda sensor

Post by CJ B »

I just checked for fault codes and the light just blinked constantly about twice a second.
I pulled the wire on the lambda sensor and went for a blast and the car didnt seem any different.
I re-checked the fault codes and it still blinks the same i.e. no fault with the lambda disconnected.
PW@Woodsport
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Re: Lambda sensor

Post by PW@Woodsport »

thats odd? it should have put a code on when you disconnected and went for a blast? just to clarify...we are definately talking about the lambda sensor and not the cat temp probe instead? its easy to get the two mixed up...ignore what im saying if you clearly know the difference.
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CJ B
Posts: 366
Joined: Wed Dec 15, 2004 1:15 pm
Location: Northwich (not Norwich)

Re: Lambda sensor

Post by CJ B »

easily confused me - have we met?
I will double check :clown:
CJ B
Posts: 366
Joined: Wed Dec 15, 2004 1:15 pm
Location: Northwich (not Norwich)

Re: Lambda sensor

Post by CJ B »

Been to have a look and its the thingy thats about 3-4" long secured by two bolts that appears to stick up from the top of the cat / turbo elbow.
It looks exactly like what was described by my local garage as a lambda sensor when I MOT'd my 200sx (they were deliberating wether it should meet 'cat' standards or not) , apart from that it could be the flux capacitor or a widget for all I know :S

I noticed just now that the car is running with reduced boost - is this because the disconnected sensor is telling the ECU that the engine is cold?
I will reconnect tomorrow when it is light and hopefully not as cold and windy.
If any one local wants to meet up for a quick bevvy and have a look at my car and tell me what is standard and what is not / fooked then I will definitely get the first pint!

Cheers,
Chris.
CJ B
Posts: 366
Joined: Wed Dec 15, 2004 1:15 pm
Location: Northwich (not Norwich)

Re: Lambda sensor

Post by CJ B »

Looking at the pictures on ebay of gtschris oxygen/lambda sensor I can say - THATS THE bu88er

http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... eName=WDVW
PW@Woodsport
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Joined: Tue Dec 14, 2004 6:40 pm
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Re: Lambda sensor

Post by PW@Woodsport »

yep its the O2 sensor,worth checking though! im a bit confused why disconnecting it hasnt thrown an error code up? but the reason its not boosting properly is cos the ecu has gone into safety mode and limited your boost,it will also have pulled your ignition timing too.

Are you handy with a multimeter? if you put it on 20v and attach one probe onto the black wire (while its connected) on the lambda sensor and the other to earth you should see a fluctuating voltage reading ranging from 0.1 to 0.9 volts at idle....then at revs the reading should hover around the 0.45v mark....if so then your sensor is working fine.
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CJ B
Posts: 366
Joined: Wed Dec 15, 2004 1:15 pm
Location: Northwich (not Norwich)

Re: Lambda sensor

Post by CJ B »

I reconnected it and the car is boosting more but it doesnt hit the top of the scale and I remember my GT4 it used to go beyond maximum (3rd gear foot to floor)
I'm gonna do the multimeter thing and check that but I'm guessing there is a leak somewhere or a few blades missing from the compressor wheel.

Paul, I read your profile and ended up reading through the whole of your V6 conversion. When I got to the end the link for the soundfile went to the old imoc site :(
How is the car, how does it handle and what kind of insane acceleration does it pull. Also have you had the finished product weighed?
Cheers,
Chris.
PW@Woodsport
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Re: Lambda sensor

Post by PW@Woodsport »

oh bu88er,that link does indeed go to the old imoc site,anyone care to host a soundfile of the V6 running until imoc gets up and running again?

I havent finished the project as a whole just yet,so i havent driven it in anger,only backwards and forwards to make sure nothing is goung to fall off! theres brakes and suspension to do and a bit of welding before she hits the roads.Im expecting the practically vertical torque curve from this engine to make it pretty insane alright,wont know for a few months though.

If you want to hear the soundclip of it running email me and i will send it to you directly until some good fellow on here hosts it for me.
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David Broad

Re: Lambda sensor

Post by David Broad »

Quick Q related to the sensor, mine is dead also and am looking to get a new one. Question is for a rev 2 tubby do i need the single wire or 4 wire?
couldnt_think_of_a_name

Re: Lambda sensor

Post by couldnt_think_of_a_name »

David Broad wrote:Quick Q related to the sensor, mine is dead also and am looking to get a new one. Question is for a rev 2 tubby do i need the single wire or 4 wire?



Single


J
David Broad

Re: Lambda sensor

Post by David Broad »

Cheers
Terry

Re: Lambda sensor

Post by Terry »

When I got my car the lambda sensor wasnt connected either. Thought this to be a bit strange, the wires were just cut.
(Would prob account for the large amounts of black smoke tho :cry: )

Anyhows, this also didnt put the MIL on, then I found the Mines ECU!! :?
couldnt_think_of_a_name

Re: Lambda sensor

Post by couldnt_think_of_a_name »

Terry wrote:
Anyhows, this also didnt put the MIL on, then I found the Mines ECU!! :?



Lucky bu88er !!
Terry

Re: Lambda sensor

Post by Terry »

Got rid of the Mines now tho, couldnt map it and cant get much info on them.... :cry:
CJ B
Posts: 366
Joined: Wed Dec 15, 2004 1:15 pm
Location: Northwich (not Norwich)

Re: Lambda sensor

Post by CJ B »

Just out of interest which error code would you expect?
I looked thrugh a page of codes and didnt see a 'lambda/o2 is stuffed' number.

Anyone know the most accurate list of codes?
Terry

Re: Lambda sensor

Post by Terry »

I would of expected code 21. Oxygen sensor signal / Oxygen sensor heater circuit.
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