my truck stumbles when you start it and within 5 seconds or so clears up and runs smooth…any ideas on the prob? i changed the fuel filter , still the same result.
The first thing I would do is remove air cleaner and adaptor with breather hose attached to it and take a look after it’s sat for a few hours and see if there’s fuel pooling on top of throttle body. If so most likely culprit is fuel pressure regulator which is located in the fuel injector assembly attached to TB.