Symptoms:
Intermittent misfire with white smoke out of exhaust (more smoke when accelerating during misfire condition)
Intermittent hard to start
Occasional P0305 (cylinder 5 misfire), but not immediately/always when misfiring
Begins when engine returns to idle; will not begin misfiring once cruising on the freeway, only in stop/go situations
Can prevent misfire from starting by keeping load on engine (left foot braking with small load on idle)
When misfiring, I can disable injector #2, cylinder #5 with no apparent change in misfire. Disabling any other injector will result in running even rougher.
Clears up: sometimes randomly on its own, sometimes under braking, sometimes with a blip of the throttle, sometimes moving gear selector between P, R, and D
Frequency: anywhere between 10 seconds and 7 days between issues
What I’ve done over then past 1 month (7000 miles):
Replaced injectors + supply tubes, FCA, crank position sensor, FASS pump (failed in the midst of this saga), fuel filter and water separator, rocker box wiring harness for injector 5/6
Rail pressure and supply pressure are not abnormal during misfire
Tightened grounds from battery to body/engine, and engine to ECU
Killed each injector individually using SnapOn scanner, Cyl #5 Injector #2 sounds roughest when killed and takes many seconds to smooth out when turned on. Other injectors all smooth out within 1 second when enabled again.
Inspected A/C wiring
Swapped injector wiring harness between 3/4 and 5/6 with no change (still P0305)
Filled at all different gas stations, not all bad fuel from same station
Please help!
Intermittent misfire with white smoke out of exhaust (more smoke when accelerating during misfire condition)
Intermittent hard to start
Occasional P0305 (cylinder 5 misfire), but not immediately/always when misfiring
Begins when engine returns to idle; will not begin misfiring once cruising on the freeway, only in stop/go situations
Can prevent misfire from starting by keeping load on engine (left foot braking with small load on idle)
When misfiring, I can disable injector #2, cylinder #5 with no apparent change in misfire. Disabling any other injector will result in running even rougher.
Clears up: sometimes randomly on its own, sometimes under braking, sometimes with a blip of the throttle, sometimes moving gear selector between P, R, and D
Frequency: anywhere between 10 seconds and 7 days between issues
What I’ve done over then past 1 month (7000 miles):
Replaced injectors + supply tubes, FCA, crank position sensor, FASS pump (failed in the midst of this saga), fuel filter and water separator, rocker box wiring harness for injector 5/6
Rail pressure and supply pressure are not abnormal during misfire
Tightened grounds from battery to body/engine, and engine to ECU
Killed each injector individually using SnapOn scanner, Cyl #5 Injector #2 sounds roughest when killed and takes many seconds to smooth out when turned on. Other injectors all smooth out within 1 second when enabled again.
Inspected A/C wiring
Swapped injector wiring harness between 3/4 and 5/6 with no change (still P0305)
Filled at all different gas stations, not all bad fuel from same station
Please help!
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