I installed my wideband last night and I noticed my AFR at idle seems to be extremly lean. Is this normal? It sits anywhere from 15.7 to 17.0. The car is on the stock tune. Only thing done is exhaust and boost controller. Any help is appreciated.

 

Its not normal check vaccum lines and check the fuel pressure vacuum line which goes into the manifold.

 

I checked the line you requested and it looks to be in good condition. The previous owner also zip tied both ends of that hose it looks like. I checked all the lines going to and from my boost controller and they are all still connected. Is their other vacuum lines that I need to check and if so which ones and where are they located.
Also I'm noticing and exhaust smell in the cab at idle I noticed it about 2 weeks ago and didn't think much of it until installed by AFR gauge and notice it lean at idle.
While cruising around at operating temperature the AFR sits between 14.7-15.3. While under full load it goes straight to 10.0. So I'm wondering if I don't have an exhaust leak somewhere causing lean condition at idle. But if it is an exhaust leak wouldn't the afr be off at all load? And also if the AFR was truly that lean at idle wouldn't I be getting a CEL?

 

i do have the same with my vehicle as follow :-

1) boost leak test
2) vacuum leak test
3)exhaust leak test
4) Fuel pump relay might be need to be replace & check all the fuel feed lines.

please let me know if u resolved the issue.