Hi everyone,
Sorry in advance for the long post. I'm having an issue with my 2001 S3 AMK, it failed it's MOT on emissions saying the CO levels were too high. Also my MPG had dropped from 27 to 24mpg at the same time the fault appeared:
Fast Idle Test:
CO - limit 0.3 - actual 0.77 (FAIL)
Lambda - limit 1.03 - actual 1.01 (PASS)
2nd Fast Idle Test:
CO - limit 0.3 - actual 0.21 (PASS)
Lambda - limit 1.03 - actual 1.05 (FAIL)
Natural Idle Test:
CO - limit 0.5 - actual 0.17
there is also a fault code:
16804 - Catalyst System Bank 1
p0420 - 35-10 - Efficiency Below Threshhold
That fault code started off with intermittent after it but after a week changed to the one above and then a week after that the engine warning light came on and that was the only fault listed.
It's still in the garage at the moment, there was a blowing from the front of the exhaust which turned out to be a cracked exhaust manifold, that's been replaced now and because the turbo seals had gone I got another from CR Turbos to replace that.
At the start of the year it had new cats and downpipe (oem equivilent). The garage have replaced the cats as a test to make sure they were not at fault but the fault remained so they have put the other ones back on. It also has a new Milltek cat back resonating exhaust. We were hoping that the fault was because of the cracked manifold but the exhaust is now not blowing from anywhere and the fault still remains.
The garage is going to try new lamda sensors tomorrow but they are not convinced it will fix the issue.
They told me they can hear the cam chain rattling a bit which probably means the cam chain tensioner is on its way out and there is some weaping around where the injectors go into the manifold, but we're not sure if either of them would cause that fault.
I have also tried giving it a good "Italian Valet".
The car got a new MAF about 5 years ago. and the car has done a total of 160k miles.
Anyone got any ideas for if the new lamdas don't fix the issue?
Cheers
Sorry in advance for the long post. I'm having an issue with my 2001 S3 AMK, it failed it's MOT on emissions saying the CO levels were too high. Also my MPG had dropped from 27 to 24mpg at the same time the fault appeared:
Fast Idle Test:
CO - limit 0.3 - actual 0.77 (FAIL)
Lambda - limit 1.03 - actual 1.01 (PASS)
2nd Fast Idle Test:
CO - limit 0.3 - actual 0.21 (PASS)
Lambda - limit 1.03 - actual 1.05 (FAIL)
Natural Idle Test:
CO - limit 0.5 - actual 0.17
there is also a fault code:
16804 - Catalyst System Bank 1
p0420 - 35-10 - Efficiency Below Threshhold
That fault code started off with intermittent after it but after a week changed to the one above and then a week after that the engine warning light came on and that was the only fault listed.
It's still in the garage at the moment, there was a blowing from the front of the exhaust which turned out to be a cracked exhaust manifold, that's been replaced now and because the turbo seals had gone I got another from CR Turbos to replace that.
At the start of the year it had new cats and downpipe (oem equivilent). The garage have replaced the cats as a test to make sure they were not at fault but the fault remained so they have put the other ones back on. It also has a new Milltek cat back resonating exhaust. We were hoping that the fault was because of the cracked manifold but the exhaust is now not blowing from anywhere and the fault still remains.
The garage is going to try new lamda sensors tomorrow but they are not convinced it will fix the issue.
They told me they can hear the cam chain rattling a bit which probably means the cam chain tensioner is on its way out and there is some weaping around where the injectors go into the manifold, but we're not sure if either of them would cause that fault.
I have also tried giving it a good "Italian Valet".
The car got a new MAF about 5 years ago. and the car has done a total of 160k miles.
Anyone got any ideas for if the new lamdas don't fix the issue?
Cheers
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