Exhaust Leaks

If exhaust system has large leaks, exhaust system negative pressure pulses can cause outside air to be drawn into system and past O2 sensor. Vacuum or crankcase leaks can also cause a lean condition. Misfire Or Stall

If engine misfires or stalls (including running out of fuel) while vehicle is moving, a Code 44 may set. If Code 44 is intermittent, see INTERMITTENTS in TESTS W/O CODES article in this section.

Fig 1: Code 44 Schematic (Saturn) Lean Exhaust Indication

Fig 2: Code 44 Flow Chart (Saturn) Lean Exhaust Indication

Fig 3: Code 44 Flow Chart