I'm currently pulling my intake manifold and I discovered the tops of the #3 and #4 spark plugs are white. I think it's the injectors but I wonder what else could cause just these two cylinders to run lean? The DME or injector wires?

 

Scott, are you using a maf system?

 

I think the manifold causes issues here as well. There is a mod done to the stock manifold to help this. I had this done by PD as part of the development they did for me. It worked really well. The VE increased in the front Cylinders. Its free HP.

 

The engine is completely stock except weltmeister chips. I'm interested in a modding the intake manifold if it's not the injectors. I'm sending them off to witchunter tomorrow.