QuestionI have 2 automobiles that are setting P0340 codes. One is a 2004 Intrepid with a 3.5L and the other is a 2004 Concorde with a 3.5L. I've replaced the cam position and the crank position sensors in both vehicles... twice in the '04 Concorde. They continue to set the code randomly after clearing the PCM memory. Neither sets the code immediately after clearing memory but after driving, it will return... maybe the same day, maybe after a week. The '04 Concorde has now started to intermittently go into limp-in and it is also setting a P0746 AND the P0340. I changed the trans fluid & filter, cleared the memory, and after 5 days of driving, it did it again.
I've checked sensor plugs, cleaned the battery terminals, and cannot find a reason for the faults. I've had a Snap-On scanner on the Concorde and monitored the cam and crank sensors while running. Neither show anything abnormal.
I am leaning toward a PCM replacement for the Concorde because in addition to the recurring P0340, the P0746 codes, occasionally the dash lights (not headlights...) will suddenly get brighter for a couple of seconds and then return to normal. I've monitored the alternator output for erratic voltage and it is stable while I'm watching it...
I would appreciate your thoughts on this. The recurring P0340 codes, even after replacing sensors is baffling.
Thanks,
- Mike
AnswerPOSSIBLE CAUSES
INTERMITTENT CRANKSHAFT POSITION SENSOR SIGNAL
INTERMITTENT CAMSHAFT POSITION SENSOR SIGNAL
(K6) 5 VOLT SUPPLY CIRCUIT SHORTED TO GROUND
(K6) 5 VOLT SUPPLY CIRCUIT OPEN
(K6) 5 VOLT SUPPLY CIRCUIT SHORTED TO VOLTAGE
(K44) CMP SIGNAL CIRCUIT SHORTED GROUND
(K44) CMP SIGNAL CIRCUIT OPEN
(K44) CMP SIGNAL CIRCUIT SHORTED TO VOLTAGE
(K44) CMP SIGNAL SHORTED TO (K6) 5 VOLT SUPPLY CIRCUIT
(K4) SENSOR GROUND CIRCUIT OPEN
PCM - (K6) 5 VOLT SUPPLY
PCM - (K44) CMP SIGNAL
CAMSHAFT POSITION SENSOR
