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astra faild m.ot twise on imisions test(2.0 seh)

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ok ran it thru m.o.t again today and and FAILD again
this is wat the fail form says..says lambda n/a so mustin be my lamda..


EMISSION TEST: REQUIRED LIMITS:

Co-idle 8.310% 3.50% or les FAIL
Co- fast idle N/A N/A
HC 607 ppm 1200 ppm or less PASS
lambda N/A N/A

any one any ideas wat would cure this...

faild first time and replaced...
lambda sensor
air filter
spark plugs
injectors
ran it on super unleded
made sure it was wel warmd up
nice bit of reving to clear the exsaust

stil faild :( help
 
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Lambda is N/A because the emissions level it has to meet doesn't require one.

Be worth trying the AFM and CTS, the SEH has a screw you can adjust on the AFM (as it's the flap type thing), so that could have a bearing on it.
 
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Too much co2 mate i suggest that your carbon cannister is knackerd or blocked or full up and knackerd could be the cat also plus as yours got an EGR valve if so check tht too bud
 
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Carbon canister does nothing for the emissions at all, it's the vent for the fuel tank.

It wont have EGR, and probably no cat either... not that it matters as the test doesn't need one.
 
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were abouts is the cooling temp sensor?the thermostat houseing?..goin to change that the air flow and use some of that aditive..its just realy to get ot thru the test the car runs perfect as it is its just getin the test passed..
 
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i got mine from here GM as well

http://cgi.ebay.co.uk/genuine-gm-va...arts_Vehicles_CarParts_SM?hash=item3efe3aa5aa

looks like this

 
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Jesus I can't beleive someone who's into cars can't detect something wrong with emissions like that, that's seriously high.
Will feel like a new car once sorted.
CTS controls around 90% of the fuelling, others are just trims, you could always subsitute a resistor of a warm value cts reading into the connector and see if it changes, good job there was no cat, as that co would have killed it anyway.
Even my cossie runs 0.97 % CO!!
tabetha
 
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CTS is easily the biggest factor in determining the co, so would be a good place to look.
I just hook up a resistor wheel, and set it to different resistances to simulate different temps, but resistor does the same job for a few pence, if you know the resistance at certain temps, aim for 80C resistance value, then a 1/4 watt carbon resistor under 10p will tell you if that is at fault, much cheaper than simply swapping parts.
tabetha
 

nige-p

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20seh coolant temp sensor is at the back of the block in the water housing next to the cambelt see pic below(in the grey part on the left)


only other thing is as said is to tweak your air mass but be carefull as you can put the mixture to low it has an adjuster screw in the side of the top casing, but i would make sure you count how many turns you give it

pic of it below pointing down on the right in the black part of the body may be sealed with a bung or glue


only other thing is you havent given it a oil change if the car has been running rich for a long period it contaminate the oil and you will get a high CO2 reading, have seen this on quite a few cars

the SEH is not a complicated lump so should be easy to find the issue
 
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CTS is easily the biggest factor in determining the co, so would be a good place to look.
I just hook up a resistor wheel, and set it to different resistances to simulate different temps, but resistor does the same job for a few pence, if you know the resistance at certain temps, aim for 80C resistance value, then a 1/4 watt carbon resistor under 10p will tell you if that is at fault, much cheaper than simply swapping parts.
tabetha

i dont understand any of that mate so im just gona buy a new CTS and fit that and see wat it dos..
 
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20seh coolant temp sensor is at the back of the block in the water housing next to the cambelt see pic below(in the grey part on the left)


only other thing is as said is to tweak your air mass but be carefull as you can put the mixture to low it has an adjuster screw in the side of the top casing, but i would make sure you count how many turns you give it

pic of it below pointing down on the right in the black part of the body may be sealed with a bung or glue


only other thing is you havent given it a oil change if the car has been running rich for a long period it contaminate the oil and you will get a high CO2 reading, have seen this on quite a few cars

the SEH is not a complicated lump so should be easy to find the issue

nige wat way would i turn the screw on the airflow to reduce my CO
turn it back towards the bumper or faward towards the windscreen and how many turns should i give it? cheers
 
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Sorry for the mini hijack, the engine in the piccie above the 20seh, is that simply a larger version of my C14SE ?, easy swap bearing in mind must stay auto, gf has disabilities.
Thanks,
tabetha
 

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