mate of mine had a n reg classic, failed on emmissiosm, fitted a standard exhaust with 2 cats and o2 sensor, but still failed. the o2 sensor plug on his loom is damaged so sensor lug doesnt clip in.

any suggestiosn of what else would raise emmissions, or how 2 sort sensor. only way i can see it bullet connectors. or cut decent loom plug, cut old one off loom and re wire.

 

A few points.

1. Does he run a induction kit? This will upset the MAFn sensor (does on my bug)
2. Are the readings erratic? as the MAF could be up the creak.
3. Are the injectors the standard ones or have they been upgraded? As the ECU would need mapping to take that into account.

Took my bug for the MOT and with a supposidly ECU compliant intake setup, when on the emissions they were very erratic. Sneakly I was able to disconnect one of the wires as they are crimp connected as I have to swap to a MAP sensor and this settled the reading enough to pass.

Hope this helps Steve