Can a Cracked Exhaust Manifold Cause a Lean Code? 2026 Guide
📌 Quick Summary Yes, a cracked exhaust manifold can definitely cause a lean code like P0171 or P0175. During the engine’s exhaust stroke, a crack or gap creates a Venturi effect that sucks ambient air into the exhaust stream, tricking the upstream oxygen sensor into reading too much oxygen. Yes, a cracked exhaust manifold can…
