10/29/2024
Customer brought a 2014 Chevy Silverado 5.3 engine with an intermittent misfire and trouble code p0430. This truck seems someone had replaced the spark plugs and catalytic converter and didn't correct the issue upon further diagnostic with an in-cylinder I found that it had inconsistent drops while cranking this indicated a leaking valve inside the cylinder. As you can see each of the top peaks of the towers they are supposed to be even while cranking and sustaining the pressure while this truck had some at a higher PSI and the next Tower a significant drop of 9 PSI which would cause a misfire. This truck will definitely have to be sent out to a machine shop to get the cylinder heads redone