Having had an oil change service two weeks ago (& having done 2,700 miles since last year a check confirmed plugs & air filter fine) it was a surprise when MOT'd to get a CO reading at 0.20% at 2500-3000 rpm, 0.07% on idle.
Should I worry that the 0.20% reading is at the max for an MOT pass? The engine runs sweetly, at under 65k miles, & uses no more than half a litre of oil per 2k miles. The exhaust seems good - half being original (12 years old now) & everything back from the cat being from a newer car whose owner fitted a sports system.
At five previous MOT tests, the CO reading has never been more than 0.08% so I'm tempted to just cross fingers & leave it until next year - but would welcome any advice on what may avoid a further problem!
Should I worry that the 0.20% reading is at the max for an MOT pass? The engine runs sweetly, at under 65k miles, & uses no more than half a litre of oil per 2k miles. The exhaust seems good - half being original (12 years old now) & everything back from the cat being from a newer car whose owner fitted a sports system.
At five previous MOT tests, the CO reading has never been more than 0.08% so I'm tempted to just cross fingers & leave it until next year - but would welcome any advice on what may avoid a further problem!