VERY high exhaust emissions - MOT fail

[k-ro]

Basically, everything is way too high!
CO, HC & lambda are all ready massively high. MOT tester says they are the higher hes ever seen.
Before we start replacing parts, anyone got any idea why all of them would be so high?

fyi,
CO level = 8.19%
HC level = 413ppm
Lambda - 0.79

Cheers
Kev

[MaXXeH]

u got decat?

[houston]

first thing to do is scan it to see if theres any fault codes. how longs it been since its been serviced?

[daz veedub]

+1 scan, service if needed and check is de-cat on

[AudiA8Quattro]

Failed ecu coolant temperature sender.

[Wayne]

Failed ecu coolant temperature sender.

^^ This, replace it as a 1st step.

[k-ro]

Standard cat on.
Serviced just over a year and a half ago, but a couple of oil and filter changes since.

It's getting scanned for errors tomorrow, just trying to get a few clues in the meantime.
I thought temp sender, but can that throw all those out so much?


Cheers all

[Wayne]

I thought temp sender, but can that throw all those out so much?

Yes as it will think it is cold and dump in more fuel.

[mouth0502]

sorry new to the site unsure how to post how did you resolve this issue mine is doing the same thing cheers adam

[AaronGS]

Would a failed temp sender show up on VAG-COM?