https://dannysengineportal.com/engine-misfire-rough-idle-on-gm-4-8l-5-3l-6-0l-engines/
Engine Misfire or Rough Engine Idle on GM 4.8L, 5.3L, 6.0L is becoming, more common and getting harder to diagnose.
Because, GM V8 engines are very prone, to a rough idle and engine misfire when cold.
The check engine light may also come on, with codes P0300, P0171 and PO174. But, as the engine warms up, the engine misfire or rough idle tends to go away, which seems confusing.
#engineportal #misfire #roughidle #GM #automotive #leak