MOT Fail Emmisions bugger

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Druim

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4.6 HSE Reg. Feb. 1995 Failed MOT emissions

Think/hope new Lambda sensors will sort it, only have obd 2 reader but it comes up with fault P1138 HO2S Failed switching to lean bank A – assume it means overfueling hence the fail – yes I know its not the right tool….before you get on…
Sensor voltage says bank 1 = 5 volts – bank 2 = 0.06 volts

MOT Test readings:
CO 3.65% & 4.06% - Fail above 0.30% – idle 4.86% Fail 0.50%
HC 172 & 187 PPM – Pass Max 200
Lambda 0.91 & 0.89 – Fail Min. 0.95 – Max. 1.09

Question: Am I right in replacing Lambda sensors and re-check for faults? MOT Re-test…

Also wonder if the allowed CO level is correct as its registered before August 1995 and not a passenger vehicle but PLG with weight above 2500 Kg
What I can find is that test centre has to find exact match or they must allow 3.50%

Everything else was a Pass – no problems with it being on coils or steering wheel lock not working as I pointed out it only apply after 2002 which he didn’t know but rightly found in database – oh **** he said he has failed a couple of cars on that one, plonker.
 
No,the natural output for those sensors is 5v - a lean signal,so at least bank B is capable of switching.The emission readings all show a rich mixture,which the bank B sensor at least is seeing and will be trying to trim back on that bank.
What you need to do is to start the engine from cold and view the output from both sensors,within 30 secs they should both switch down from 5 - 0v and then start cycling back and forth while the engine is at idle or cruise.If they stay down at 0v then you have your problem - its just running rich,then you have to find out why.
Does the car have LPG ?
 
how does the engine perform does it feel down on power?
a faulty air flow meter wont show a fault code but will send you down the wrong route of diagnosis as 99% of the time a faulty maf on a petrol will throw up lambda sensor faults!
 
4.6 HSE Reg. Feb. 1995 Failed MOT emissions

Think/hope new Lambda sensors will sort it, only have obd 2 reader but it comes up with fault P1138 HO2S Failed switching to lean bank A – assume it means overfueling hence the fail – yes I know its not the right tool….before you get on…
Sensor voltage says bank 1 = 5 volts – bank 2 = 0.06 volts

MOT Test readings:
CO 3.65% & 4.06% - Fail above 0.30% – idle 4.86% Fail 0.50%
HC 172 & 187 PPM – Pass Max 200
Lambda 0.91 & 0.89 – Fail Min. 0.95 – Max. 1.09

Question: Am I right in replacing Lambda sensors and re-check for faults? MOT Re-test…

Also wonder if the allowed CO level is correct as its registered before August 1995 and not a passenger vehicle but PLG with weight above 2500 Kg
What I can find is that test centre has to find exact match or they must allow 3.50%

Everything else was a Pass – no problems with it being on coils or steering wheel lock not working as I pointed out it only apply after 2002 which he didn’t know but rightly found in database – oh **** he said he has failed a couple of cars on that one, plonker.

2 New Lambda sensors fitted, 25 miles run, caught last MOT slot before weekend &

PASS :)

MOT Test readings:
CO 0.06% - Pass below 0.20% – idle 0.01% Pass Max 0.30%
HC 35 PPM – Pass Max 200
Lambda 1.02 – Pass Min. 0.97 – Max. 1.03

Glad the money wasn't wasted as some said:D Polluting no more than a Princess fart on a windy day;)
 
You were lucky,I can only assume the fault codes were old - or at least half your money and one oxy sensor was wasted.
I wish I could run my business like that and get away with it - we call it the parts shotgun,fire parts at it hoping it will effect a cure.... Imagine how you would feel if I suggested replacing those parts to "try" lowering emissions.Would you want to pay the bill if it didnt work ?
 
You were lucky,I can only assume the fault codes were old - or at least half your money and one oxy sensor was wasted.
I wish I could run my business like that and get away with it - we call it the parts shotgun,fire parts at it hoping it will effect a cure.... Imagine how you would feel if I suggested replacing those parts to "try" lowering emissions.Would you want to pay the bill if it didnt work ?

What a load of b....

Very happy i avoided your "business"
 
What a load of b....

Very happy i avoided your "business"

I'm glad you did too - you clearly have no understanding of adaptive closed loop fuel injection - nor a basic understanding of when someone is trying to help you in an organised, methodical way.
 
I'm glad you did too - you clearly have no understanding of adaptive closed loop fuel injection - nor a basic understanding of when someone is trying to help you in an organised, methodical way.

You simply don't understand how simple it was to change out the faulty part, signal frozen rock solid indicates it probably are faulty when also the fault code say so - weighing up the odds - it's probably faulty - also might have done 100K+ miles so therefore changed out both - no money wasted - MOT same day - Happy Camping didn't even have to pay for some nerd to organise in speculated methodical ways to over-complicate the problem.
 
If you are so skilled in the art of holding a 17mm spanner why did you even bother asking if changing oxygen sensors was necessary ?
It would of helped if you had also told us where the sensor outputs were sticking - at 0 or 5v - you didnt mention that in any previous posts.
You have a code reader so you are obviously interested or want to save money by doing your own repairs - are you too stupid to realise that someone is trying to encourage you to look a little further,develop your understanding of your car ?
 
If you are so skilled in the art of holding a 17mm spanner why did you even bother asking if changing oxygen sensors was necessary ?
It would of helped if you had also told us where the sensor outputs were sticking - at 0 or 5v - you didnt mention that in any previous posts.
You have a code reader so you are obviously interested or want to save money by doing your own repairs - are you too stupid to realise that someone is trying to encourage you to look a little further,develop your understanding of your car ?

You obviously cant even read, who's the stupid one gonzo?
From first post:
Sensor voltage says bank 1 = 5 volts – bank 2 = 0.06 volts
fault P1138 HO2S Failed switching to lean bank A

Now be quit - this leads nowhere - benefit nothing apart from your faint ego
 
Do you mean be quiet ? Yes I can read,probably better than you can spell.in your first post you gave no indication that the voltages were frozen - they are just numbers,all you can glean from them is that bank b had switched down rich.(They are meant to cycle around once a second.)
Calling people names is very childish,and I'm not interested in my, nor your ego.I only posted a response to your question to help you fix your car and save some money.That you choose to be rude is your choice,I cant be bothered with people who dont want to learn.
 
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