Why This Engine Ran Rough Only on Cold Mornings: An Intake Gasket Leak Log
The Silverado had been to two shops before it reached us. Both shops documented “intermittent lean codes P0171 and P0174” and “no fault found at time of inspection.” One shop had cleaned the MAF sensor. The other had replaced the PCV valve. Neither repair changed anything because the problem disappeared the moment the truck sat […]