P0174 GMC - SES after Arco... new engine, new OEM fuel injector set, etc.

Question

2001 GMC Savana complete engine replacement with new GM crate engine. Replaced complete fuel injector set with AC Delco OEM set at same time engine was replaced. New fuel filter, new air filter, new PCV valve, etc. 1500 miles after engine replacement, I stopped at Arco gas station and filled up. SES light went on before I even left the gas station and stayed on until next day. Ses light went off on its own and stayed off. 1000 miles later, van passed smog but came up with P174 Bank 1 and Bank 2 codes during the smog inspection. Any suggestions? Was it bad gas that day at Arco, or should I be concerned about anything further?

Answer 1

Hi there,

Low fuel pressure can cause the lean codes to appear and also a bad mass air flow sensor. Typically when it's on both banks like this it's a fuel pressure issue.