Co2 reading high? why
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Not many rules really, this board being aimed at technical issues, it shouldn't fall foul (hopefully) of some of the more personal issues that can affect forums.
Rule 1 - Is that you need to think very carefully before posting anything technical or asking anything technical relating to the security system of the car - See 'Security Issues' sticky for more info.
Rule 2 - We (MGF Register) do not support copyright infringement and therefore references to CD ROM, PDF versions or paper copies of the workshop manual (for instance) should not be posted on the forum. We don't want to get into trouble and we'd rather sell you a genuine hard copy through our Regalia shop anyway!
Because advice is honestly and freely given in this technical section, much of it will be amateur experienced based, so any information is given in good faith and is not guaranteed as correct.
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Co2 reading high? why
MGTF 135 year 2003 64k miles
I took the car for its french MOT today, passed except Co2 reading was 0.7 when its a 0.3 max.
Inspector thinks it might have an ex leak before the lamba sensor?
history is that last week we put a new head gasket with timimg belt and water pump.
Used a good head from a 1997 120 bhp car had it skimmed , and used the cams etc from the 135.
Apart from that no issues.
Where to start with looking for and solving this?
I took the car for its french MOT today, passed except Co2 reading was 0.7 when its a 0.3 max.
Inspector thinks it might have an ex leak before the lamba sensor?
history is that last week we put a new head gasket with timimg belt and water pump.
Used a good head from a 1997 120 bhp car had it skimmed , and used the cams etc from the 135.
Apart from that no issues.
Where to start with looking for and solving this?
- talkingcars
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Re: Co2 reading high? why
I would start by looking for air leaks.
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Re: Co2 reading high? why
Inlet or exhaust side?talkingcars wrote:I would start by looking for air leaks.
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Re: Co2 reading high? why
I was told that HC being high would be the result of leaks and not the CO2 readings.
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Re: Co2 reading high? why
An exhaust leak before the first lambda probe can cause a misrepresentation of the exhaust gases which causes the ECU to adjust fuelling.
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Re: Co2 reading high? why
Just found that when we finished the head gasket repair, forgot to connect the air box to the throttle body
Lots of air going in and maybe a high Co2 reading?
Lots of air going in and maybe a high Co2 reading?
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Re: Co2 reading high? why
Cannot see that making much difference. On Blue it was a faulty CAT................ a faulty new CAT at that.
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Re: Co2 reading high? why
My VVC failed its emissions test once due to a leaking gasket betwixt the exhaust manifold and downpipe, and a very small leak at that.
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Re: Co2 reading high? why
Ditto. Replaced mine with a Bose cat and all good.Plezier wrote:Cannot see that making much difference. On Blue it was a faulty CAT................ a faulty new CAT at that.
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Re: Co2 reading high? why
First thing will be put it on the ramp we have here, and look for exhaust leaks.
then see where we go.
then see where we go.
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Re: Co2 reading high? why
Good luck as I know full well just how frustrating tryign to solve this can be.