Supernova69

I have a 1969 nova that I put a 2001 ls engine in. It's a 5.3. I also the biggest cam I could get without changing heads on it. Before I put the cam in, I had no problems with my tune. I went to a SD tune with the cam. At idle the car is fine on o2 sensors. WOT the o2 sensors are fine. When I let off the throttle completely when I am going down the road b1s1 reads really lean and asks for more fuel than at WOT. It only does this when I let off completely and only on b1s1. New o2 sensors and I put a new intake gasket. Any ideas or help would be appreciated. Thanks

aknovaman

iTrader: (7)

header gasket leak?

Supernova69

I don't think so because I haven't messed with my manifolds since I put the engine in and it didn't have that problem before I put my cam in.