Oxygen Sensor Relay location?
 

can someone tell me where I find it on my '86 911? thanks

It is in the DME relay,terminal 87 b,located under the drivers seat next to the DME unit. Its held in place by a 10 mm nut.
Howard

thanks - I was under driver's seat 2 weeks ago - changed out the DME relay - I don't think I saw any other relay. Do you mean it is handled by the DME relay or is it a separate relay? confused...

The cell in the oxygen sensor (rich lean voltage) goes directly into the DME. The heater for the oxygen sensor comes on with the fuel pump (un-fused).

The o2 sensor heater is handled by the DME relay terminal 87B.
Howard

ok guys thanks - didn't think there was separate relay for it. OK, moving on to the next possibility. Un-heated garage limiting my wrenching.. January thaw should be coming...

Cylinder Head Temp Sensor needs updating to 2 wire type?
Good write up here: Pelican Technical Article: Cylinder Head Temperature Sensor - Upgrade for 84-89 Carrera

What function do you think the Oxygen sensor relay is not doing?

You aren't coming from an Audi Lamda CIS system are you?

no audi lamba CIS. No, been going through a checklist troubleshooting a rough idle and missing/stumbling on acceleration. Still got to do plugs and fuel filter. Did rotor, cap, wires, DME relay.. Don't see any loose wires or vac hoses. 50's end of week may let me finish basic tune-up stuff.

Ckt
 

http://forums.pelicanparts.com/uploa...1357681234.jpg

ok - DME, wires, fuel filter, cap, rotor, - no change; still won't fire properly on acceleration - after I do plugs the last resort will be the Italian tuneup..