VW Polo failed NCT emissions test at low idle

mikefoxo

Brought it in about 2 weeks ago and she failed. It's normally been very reliable in the 7 years I've owned it. Put a half bottle of Dipetane in it and revved the crap out of it, brought it back to the mechanic but still the same. He said something like an air leak in the exhaust manifold or worn valve guides:eek: Looks like I have to bring it to a specialist.

I see there's a few threads on this but they all failed on high idle, not low. Anyone been through this before?? Thanks

Toyotafanboi

If it's the 1.2 3 cylinder, people seem to repeatedly go through a false hope period of replacing MAF sensors, oxygen sensors, catalytic convertors, throttle bodies, coil packs and so on and so on when inevitably they need a cylinder head refurb and by the time they've replaced all the things that weren't broken the head refurb is often financially unviable.

Can you post the exact emissions readings? Is it a 1.2 engine? What mileage?

mikefoxo

Apologies for only getting back to you now. I've seen some of the other threads alright. There's been no mention of replacing any catalytic converters or anything like that, he did try a new sensor of some sort but it didn't work so put in the old one. I don't have the test sheet with me, gave it to the mechanic . It is a 1.2 engine and it has 52k miles on it if I remember correctly