Emissions problem for Irish NCT
I could do with some ideas here or my Alfa 155 ownership will reach a sad end when I sell it for scrap.
My 1994 155TS 1.8 8v went for the Irish NCT (of which the UK equivalent would be the MOT test). Here, they check the exhaust emissions and the limits are strict. My 155 is OK at a low idle speed, but at a 'high idle' (about 2500rpm) it reads 0.85ppm CO2. The upper limit is 0.3.
I had work done on it in a dealer. They replaced a lambda sensor, and told me that the airflow meter also needed replacing. A new one would have been >€500 before fitting, which is more than the car is probably worth. I got a s/hand one and they fitted it, and they said it was OK.
When I went for the test some weeks later, it failed on the CO. Now, two possibilities come to mind: 1. The garage said it was OK just to get rid of me; 2. Unluckily, the s/hand airflow meter failed between the time it was fitted and the time of the test.
Anyway, I'd appreciate any tips on what might help to bring the CO emissions down. It's not the cat or the lambda probe that are at fault. Do injector cleaners actually do any good?
The nearest Alfa dealer is more than 50 miles away from where I live, so it's not easy driving back again and again to get things sorted. Any quick fixes out there?
One issue which may be relevant is that the car tends to 'kangaroo' in first and second when moving off. This may indicate a weak mixture or some other problem. I'm not sure if it has any influence on the emissions.
It looks like I will have to sell the car for parts if I can't sort this out. The costs to keep something on the road are crazy if an injection/exhaust problem like this becomes difficult to sort out.