Weber 38 DGAS part identification

[@mjlambersonz]

I think it's actually a vacuum port?

[@josemariajosmasarrisarraga5224]

Air , the air of the mix... open more air...

[@mjlambersonz]

Did you ever figure it out?

[@oceanofdevotion9405]

Air fuel mixture

[@philipb.7889]

Thanks! Any idea what a good baseline setting would be? I never checked it when I removed it... It's installed on my '92 V8 Landrover Defender.

[@oceanofdevotion9405]

@@philipb.7889 Warm car up,. At idle,take screw in til motor starts to stumble ,,back out half a turn