Pre facelift Rev counter wiring

[P_VIDDY]

Anybody know what wire it is forthe Rev counter on a pre facelift 1987 325i?

Worked before fitting m52 so guessing I have wrong connection at c101

Thanks

[Brianmoooore]

It's still a black wire, but it's in a little 3 pin plug and socket that originally went between the near the instrument cluster and near the ECU.
IIRC, it also carries the road speed signal which the M52 will need to keep it happy.

[P_VIDDY]

Sorry but that has lost me? So Rev counter doesn't go through c101?

Apologies if I am just being simple

[Brianmoooore]

So Rev counter doesn't go through C101

Not in some pre facelift stuff. Look for a plug hanging down from the loom that goes to the cluster, and a matching one on your old engine loom, near the ECU.

[P_VIDDY]

Ah brill. I'll check tomorrow. Thanks

[P_VIDDY]

Brian... You are a legend! Rev counter now working