Technical High CO emissions

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Technical High CO emissions

At idle B1 02v is fluctuating at.3 to .8v
B2 02v is mostly steady at 0.05v but every 10 secs or so climbs to around .6v and straight back down to 0.05v
 
At idle B1 02v is fluctuating at.3 to .8v
B2 02v is mostly steady at 0.05v but every 10 secs or so climbs to around .6v and straight back down to 0.05v
 
At idle B1 02v is fluctuating at.3 to .8v
B2 02v is mostly steady at 0.05v but every 10 secs or so climbs to around .6v and straight back down to 0.05v
.


Is that with air leaking into manifold through open evap pipe?



Please post the map sensor reading with the evap pipe open and with it plugged?
And what it reads at zero rpm.

Can you please refit the original map sensor and post the readings you get from it under the same tests as above.

If your scan tool can display info on in graph form please post graph of o2 sensor number 1 volts at normal idle and fast idle . Please do this with both map sensors.
 
Now at warmed up idle LTFT IS steady at -15% & STFT is fluctuating between +8 & -10%
That is massively better.
Sorry I wrote my last post as you were posting the above.

if the improvement is due to evap pipe being left open and leaking air into inlet manifold it is very strange , because the vacuum in the inlet manifold should not change ,the ecu will close the throttle butterfly a little to compensate for the air leak in order to maintain the idle rpm.

Short term fuel trim slight fluctuation like you are seeing is normal.
 
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All of today's tests are with original MAP sensor as I refitted last night.
Good man that could be why you are seeing improvements, not certain but possible.

The short term fuel trim reacts quite quickly to changes the long term fuel trim takes much longer to adjust.
 
With evap pipe completely open the rpm increased at idle to over 950rpm therefore a non starter therefore I partially blocked which brought down rpm to 770 and gave the readings described on previous page. MAP at 0rpm =29 inHg.
At idle is 9inHg
At fast idle is 7.4
 
With evap pipe completely open the rpm increased at idle to over 950rpm therefore a non starter therefore I partially blocked which brought down rpm to 770 and gave the readings described on previous page. MAP at 0rpm =29 inHg.
At idle is 9inHg
At fast idle is 7.4
Those readings look noticeably different to the readings taken from your photos of scan tool when new map sensor fitted.

I think you are doing well.

Good job sticking with it.

You may wish to now try totally blocking evap pipe and see if engine settled at idle with o2 sensor 1 voltage fluctuating and fuel trims looking ok (long term fuel trim under 25 is ok in my view)


Fuel trim for o2 sensor 2 is as far as I know meaningless as your car does not have wideband o2 sensors. So ignor it.
 
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Just took for MOT and emissions were 0.1 at fast idle and 0.14 at idle so passed.
Gonna clean all evap pipes and carbon filter. And hopefully will fix.
 
Just took for MOT and emissions were 0.1 at fast idle and 0.14 at idle so passed.
Gonna clean all evap pipes and carbon filter. And hopefully will fix.
Eeeeek

DO NOT BLOW AIR DOWN ANY AIR LINE TO EVAP CANISTER , it could catch fire
iirc

Seriously doubt the evap lines and canister have caused your problems , the evap pipe to manifold is only briefly and periodically open to canister when certain running conditions are met. Worth visual check of the pipes for holes or other leaks though.


To me looks like it was rubbish new map sensor was faulty and cause of all the emissions problems.

So it is fixed already , yay

Thanks for telling us the outcome
Great result

Thanks
 
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id reconnect the evap pipe. Take it for a nice dive and get it nice and hot then immediately retest with the scanner and take it from there. I have a feeling the original MOT left it before testing and it will not require any further work finger's crossed


The purge valve rarely fail and is nearly always due to over filling
 
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