Possible Causes
- Snow, plastic bags or other foreign material may restrict airflow at air inlet.
- Misrouted air cleaner ducting.
- On engines recently repaired, rags or cap plugs may have been inadvertently left in an air inlet pipe.
- Exhaust Back Pressure (EBP) device may be closing during cranking or stuck closed.
- Tailpipe or muffler may have collapsed or been damaged.