Failed NCT - Emmissions

Uncle Mclovin

Golf 2003 1.6 Petrol

Burning oil

Last full service - 6 months ago

Exhaust Emmission

Low Idle - CO 0.10 vol%; HC 51ppm
High Idle - Lambda 0.98; CO 0.65 vol%; HC 117ppm

The car only failed on the CO on high idle.

I'm looking to trade in the car soon so hoping to just get it through the NCT.

I've read about Dipetane. Is it worth giving it a go and driving it hard and chancing it or are the levels of CO unlikely to be reduced enough to pass?

Any advice is much appreciated.

*Kol*

Did you check your exhaust for leaks?

Uncle Mclovin

*Kol* wrote: »

Did you check your exhaust for leaks?

No I didn't really do anything yet. Was just looking for some tips.

Is a leaking exhaust the main reason for high CO2?

jimgoose

Uncle Mclovin wrote: »

No I didn't really do anything yet. Was just looking for some tips.

Is a leaking exhaust the main reason for high CO2?

No, it's CO, not CO2 and excess of that generally means too much fuel and/or not enough air. That Lambda figure seems to indicate things are slightly on the rich side as well. If I were you I'd get the OBD codes read, if any, and look at the MAP/MAF and air-intake.

Uncle Mclovin

jimgoose wrote: »

No, it's CO, not CO2 and excess of that generally means too much fuel and/or not enough air. That Lambda figure seems to indicate things are slightly on the rich side as well. If I were you I'd get the OBD codes read, if any, and look at the MAP/MAF and air-intake.

Thanks.

I'd say I'll get a mechanic to take a look. Probably the best option.

arthur daly

Op it's burning oil??if so that's your problem no fuel additive will cure this,it is caused from poor servicing from new wearing the piston rings and liners causing oil to enter the cylinder.
Your only hope is bardhal stop smoke oil additive but even that might not cure it,basicallyit thickens the oil to stop it leaking into ccylinder

nct tester

a spurious cat might be good enough to get it through the retest but as arthur daly said it probably needs valve stem oil seals/permanent cure for the oil burning, as well as a cat for a long term solution.

9935452

how much oil is it burning per 1000miles.
I had a 1.4 petrol 02 golf which burned 1 litre every 3k miles with 130k miles on the clock and never had an issue with passing an nct.
Another poster here has a 1.4 bora with around 170k miles burning a litre per 1000 miles and he says he has no problem passing the test.

jimgoose

9935452 wrote: »

how much oil is it burning per 1000miles.
I had a 1.4 petrol 02 golf which burned 1 litre every 3k miles with 130k miles on the clock and never had an issue with passing an nct.
Another poster here has a 1.4 bora with around 170k miles burning a litre per 1000 miles and he says he has no problem passing the test.

And that's a good point. My yoke burns about a litre every 1,500 miles, and is one of the cleanest-running I've ever seen.

Uncle Mclovin

I'd say its burning about a litre every 1,500 to 2,000 miles. I was told this is fairly standard in Golfs once they reach a certain age.

jimgoose

Uncle Mclovin wrote: »

I'd say its burning about a litre every 1,500 to 2,000 miles. I was told this is fairly standard in Golfs once they reach a certain age.

Mmm. I'm sceptical about this oil business. A problematic amount of unregulated oil being burned would surely send the HC emissions figures mental. There's something else going on. Like I said, start with OBD fault codes.

Uncle Mclovin

Thanks jimgoose. I will get that checked out.