Well I finally got around to puting on the K&N air filter assembly back on teh Weber 48IDA and when driving it to work, it ran like ****...my A/F went from 13.5-14 at idle to 19+ and when giving it any gas it got up to around 49 or 50. It ran perfectly fine earlier today so what the hell?? My guess is to check the needle and seat. I'm hoping that it is just stuck shut but there is fuel getting to the carb. I have a pressure gauge in between my regulator and carb which is reading a steady 4.8 PSI. besides the needle and seat, any ideas on what is going on??

I have it jetted as follows:
65 idle
190 main
155 air
40mm venturies
60 pump jets
3.3 needle & seat

thanks,
Phil

 

so this happens with or without the K&n? or both cases now?

 

both cases right now. it ran like **** with it on, so i took the top and filter off, but left the base on and it still ran the same.