Where is the lambda probe?

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johnono
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Post Fri Sep 16, 2005 10:18 pm

Lads, i need a pic of this. as im not sure wher ei should be looking.

any chance u lot may have a pic of where it is sat and what it should look like...

ill explain in time :?
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Post Fri Sep 16, 2005 11:30 pm

is Non-cat a lambda free system then?

mine is non cat and the realoem shows no lambda on a non cat system so...

is there no lambda on non cat cars?
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Brianmoooore
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Post Sat Sep 17, 2005 10:56 am

johnono wrote:is Non-cat a lambda free system then?

mine is non cat and the realoem shows no lambda on a non cat system so...

is there no lambda on non cat cars?
Trying to read and understand that this early on a Saturday has given me a headache.
Not sure if this is what you're asking, but if your car doesn't have a cat, then it won't have a lambda sensor, unless its been converted to LPG like mine, then it will have one, and will meet cat type eissions levels without one, as mine did yesterday in its MOT.
There will be a connector for a lambda sensor mounted underneath the front battery tray, but it will just have a blanking plug in it.
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Post Sat Sep 17, 2005 11:08 am

cheers brian :)

reason i ask is im a bit worried that the new system i had fitted diddnt include a fitting for the lambda, and the little tosser at the fitters diddnt plug it in...he may have just ripped it off :-x


so i need to find where the lambda woukld have gone, and then work out if mine should have had one.. i think i could do a check on the realoem with my vin number also?

anyway , i just needed to know if there are any non cats with lambdas :?
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Brianmoooore
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Post Sat Sep 17, 2005 11:21 am

Purpose of the lambda sensor is to protect the cat against overfuelling and consequent damage, so no cat, no need for a lambda sensor.
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Post Sat Sep 17, 2005 11:42 am

so could a cat equipped car run without the cat completely?

just checked th oem, and mine is non-cat equipped
jmc330i
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Post Sat Sep 17, 2005 11:47 am

johnono wrote:so could a cat equipped car run without the cat completely?
Yes, if you remove the Cat from a Cat equipped car it will run fine.
EDIT - although the emissions may be higher.

You do not need to remove the Lambda sensor if you remove the Cat.
Last edited by jmc330i on Sat Sep 17, 2005 11:53 am, edited 1 time in total.
James
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Post Sat Sep 17, 2005 11:51 am

Brianmoooore wrote:Purpose of the lambda sensor is to protect the cat against overfuelling and consequent damage, so no cat, no need for a lambda sensor.
The lambda monitors the unburnt oxygen in the exhaust gas to keep the air/fuel ratio as close to 14.7:1 as possible, as this is the optimum air/fuel ratio for combustion (stoichiometric air/fuel ratio). This keeps the engine running at a balanced point between power, efficiency and a good level of emissions.
The Cat is there to further reduce the emissions and the lambda sensor also helps the Cat do its job, and as you say also protects the Cat.

If you remove the lambda sensor, you will need to change to a 'non-Cat' ECU otherwise the engine will not run right. The 'Cat' ECU will be looking for the voltage output signal from the lambda sensor and will run in 'limp' mode if it doesnt see the signal, to protect the Cat and engine.
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Post Sat Sep 17, 2005 11:58 am

i had an emmision check the other day and i was up to 4%..the higest allowed to pass is 3.5% younger than 86 (non-cat)

i failed the mot on that...

is the % level adjustable from the small screw on the afm?
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Post Sat Sep 17, 2005 12:14 pm

johnono wrote: is the % level adjustable from the small screw on the afm?
Not sure on that one, TBH Ive never looked into it. Something is adjustable but I couldnt tell you what, sorry.
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Post Sat Sep 17, 2005 12:24 pm

the idle CO% is controlled by the bleed screw on the AFM indeed dude, get it tweked to around 1.5 but make sure the HC readings remain lower than 400, you have to balance the two to get a nice idle

the 02 sensor removal does not require the ECU to be replaced, they all have provision to run with or without, even the 073 type on chromie cars is Cat prepared

look under the battery tray for the connector and see if there is a loom running down the inner wing , no loom no 02 M8

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Post Sat Sep 17, 2005 12:37 pm

ant wrote: the 02 sensor removal does not require the ECU to be replaced, they all have provision to run with or without, even the 073 type on chromie cars is Cat prepared
Thats cool, I was told on here somewhere that there was a difference between the ECUs - I stand corrected.
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