GM recalled 1.5 million vehicles with this engine on April 14, 2009 due to risk of fire from engine oil leaking under the valve cover gaskets onto hot exhaust manifolds. The fire could spread to the nearby plastic spark plug wire retainers on the valve cover and then to the rest of the engine compartment. GM fitted the affected vehicles with redesigned spark plug wire retainers. These engines were noted for having problems with the plastic upper intake manifold cracking around the EGR passage. The engine would then hydrolock. The lower intake gaskets and upper intake manifolds were revised, correcting all these issues.