Whats the black doughnut on No.1 lead? 16v

[borders16v 0]

Was looking to change my leads again because of a misfire. Ive done rotor,plugs,leads,dis cap already but cant change lead 1 because of the little black doughnut.Its now about 7 years old and needs changing I think.

Is this a knock sensor and it plugs into the isv i think.

What to do? :cuckoo:

[Supercharged 2]

It's a firing point / knock reference sensor and should be attached to lead 4 not 1 (1 is always at the cambelt end on VW's)

 

In a knock situation it tells the ECU what cylinder bank it is for fault logging.

[Jim 2]

If you bought new leads from VW (or OE leads from somewhere like VW Spares) you'll find that you can actually unscrew the end of the leads and slip the ignition reference sensor back over the lead. In my case though I found the sensor was SO tight on the lead that it took a significant amount of effort to get it on there... might be worth buying a new reference sensor at the same time as it's easy enough to swap.

[borders16v 0]

Nice one,ta very much will do. Got my 1 and 4 *rse about t*t :D