VW Polo 1.2 - 2016 VW Polo 1.2 TSI fails first MOT on CO2 emissi

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Tue 30 Apr 2019 15:04
VW Polo 1.2 - 2016 VW Polo 1.2 TSI fails first MOT on CO2 emissi - DavFox

2016 Polo 1.2 Bluemotion (petrol). 30,000 miles. Full dealer service history. I've had the car for 6 months.

First MOT due and car just (1 month) out of warranty. I'm attaching results.

Took to local independent garage for MOT and it failed. CO2 reading 0.63%. Maximum allowed 0.20%. They told me that car of this age and mileage should not have these readings - something is wrong with it they think. My suspicions that fuel economy not what it should be for this engine are roused!

Service also due at same time so it then goes to local VW dealer for diagnostics to see what's wrong. They come back and report 0.19% CO2 and say nothing wrong. Everything checks out okay and no warnings.

Seems to drive smoother/quieter after the service so I wonder if they did something in addition to the oil change. Firmware of somesuch?

So, back to independent for re-test of emissions. Still high. See attached.

So my question here is what to do?

- take to another independent for 3rd opinion

- are VW trying to avoid having to contribute goodwill for anything that really needs fixing - as said it's just out of warranty?

- is 0.19% actually okay for a three year old engine of this type and the independent garage doesn't know that?

- if i get it passed via VW will I run into issues when next MOT due - does it get worse?

- take it up with Driver & Vehical Standards Agency?

Thanks in advance for any wisdom here!

Dave

www.dropbox.com/s/lr6t93o527qezzt/polo_emissions.p...0

Edited by DavFox on 30/04/2019 at 15:07

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Tue 30 Apr 2019 15:19
VW Polo 1.2 - 2016 VW Polo 1.2 TSI fails first MOT on CO2 emissi - bathtub tom

It seems strange to me the VW test skipped the fast idle and natural idle test. Perhaps they performed some jiggery-pokery to get it to pass?

I'm sure someone more technical than I will be along to explain.

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Tue 30 Apr 2019 15:45
VW Polo 1.2 - 2016 VW Polo 1.2 TSI fails first MOT on CO2 emissi - dieselnut

On the VW test it says at the top of the printout " Engine speed measurement was by-passed "

On the MOT one it was measured at between 2500 & 3000RPM.

I suspect that is how the fiddle was achived.

Ask VW why that was, & point out that the MOT test has to be between 2500 & 3000 RPM.

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Tue 30 Apr 2019 16:53
VW Polo 1.2 - 2016 VW Polo 1.2 TSI fails first MOT on CO2 emissi - daveyjp

You will see the independent report says 'manual check'.

From what I have observed they simply use the car rev counter for the rpm, this is why VW probably states the measurement was bypassed - they don't use the emissions equipment to measure the rpm.

I would however want to be in the VW testing area when they do the test.

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Tue 30 Apr 2019 16:13
VW Polo 1.2 - 2016 VW Polo 1.2 TSI fails first MOT on CO2 emissi - RichardW

There's clearly something wrong with it - I would have expected a 3 year old car to be near zero CO emissions, and the lambda is off too, indicating the mixture is not right. It needs to go on the diag computer with someone who knows what they are looking at, to see what the lambda sensor(s maybe) are showing, and what the coolant temp sensor is saying. Then a temperature gun check of the cat to see if it is working. Having said that, if you only every potter in it, then take it out for a damn good thrashing and get it properly hot at high RPM and see what that does for it....!

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Tue 30 Apr 2019 16:35
VW Polo 1.2 - 2016 VW Polo 1.2 TSI fails first MOT on CO2 emissi - John F

These results are not only unacceptable for such a new engine, they look as though they come from different cars. Was the cat adequately warmed up? Why are the hydrocarbon particle readings (HC) so different?

For comparison, our Focus 1.6 Zetec CO was zero at natural idle, 0.02% at fast idle, and a mere 31ppm HC....at 137,015 miles. (Of course, it is very well maintained with never more than 14,000 miles, and usually a mere 10-12,000 miles, between oil changes :-)

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Tue 30 Apr 2019 16:54
VW Polo 1.2 - 2016 VW Polo 1.2 TSI fails first MOT on CO2 emissi - gordonbennet

JohnF, you are such a tease :-)

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Fri 3 May 2019 21:22
VW Polo 1.2 - 2016 VW Polo 1.2 TSI fails first MOT on CO2 emissi - privateinvestor

I would Check all the filters - have they been changed, fill up with Shell V power petrol (full tank), take it on the motorway or equivalent for a full 30-45 mins hard and fast (3rd and 4th gear) drive with some injector cleaner added as well. Then take to a different MOT station and get tested.

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