Lambda

If I put a new exhaust back box on (without a lambda hole!) do I need to drill one or can it be disconnected?
What happens without a sensor?

People have reported that if you leave the sensor connected electrically and just tied up out of the way, the ecu accepts that and carries on as normal.
Because it is sensing clear air.:yesnod:

To make sure the engine is working at peak efficiency it would be better to drill a hole.
Your choice, really.:shrug:

I have seen ads for devices that install in the harness place of the lambda sensor and fool the ECU into thinking it is still there.
Alternatively any welder or exhaust shop can weld a bung in place to attach the Lambda as normal.

Rich

Talking from personal experience with my '93 montego 2.0i running Lucus engine managment leaving the lambda probe disconnected resulted in a 8% oxygen reading so the system thought it was running extemley lean so was dumping more fuel in than the exon valdias.

I would get a boss welded in.

With my TT mk4 I fitted a mil eliminator from MGF centre