The engine on my 2000 Grand Caravan Sport with a 3.3 Flex fuel engine will not start following replacement of Cam position sensor and Crankshaft position sensor. I replaced them due to engine starting to buck and OBD-II code of P1391 that stated intermittent loss of cmp or ckp. Now the engine wont start and the OBD code is P0601 which says PCM internal fault condition. Anyone have any experience with this and how to fix?

 

The cardboard spacer on the tip of the sensor is there to maintain correct clearance for the sensor? Did you leave them on? Did you disconnect the battery when installing? You may have inadvertently shorted something to ground to create the 601. Inspect the wire harness from the sensors to the PCM. Verify you're getting the reference voltage at each sensor.

I've read a 1391 can be a cracked flex plate. You'll have to inspect it or remove the tranny to verify.

 

Cougar,
Thanks for the info. I did disconnect the battery and was very careful about installing the new sensors. I left the cardboard spacers in place as well. All the wires appear to be intact and the engine turns over fine but will not fire. May have to check the distributor now and hopefully that is the cause. I really dont want to remove the transmission as I cant do that at home.

Randy

 

Might try putting the old cam sensor back in to see if that changes anything. The crank sensor is usually the culprit for engine cut outs and bucking. 97 and up the cam sensor primary function is to set timing info at start up. After that it's only used as a comparator to the crank sensor for fault status. Distributor on a 3.3 ????

There is an inspection plate on the bottom of the bell housing on a 4 speed 41TE tranny. Sometimes a cracked flex plate can be detected there or by removing the starter. Unfortunately, there are times when it can only be detected by removing the tranny to get a good look.

Got a hunch you know this but just in case the ring gear on the flex plate is what the crank sensor senses to generate it's timing signal. If the plate is cracked and sometimes the bolts sheer, the plate "wobbles" creating erratic sensor data. You see it as hard starting, bucking, stalling.

 

I guess Im still old school, its the ignition coil pack and not called a distributor anymore. I will keep you posted on what I find out. Thanks for the update.

 

Still no luck on starting but I have noticed that after the engine cranks that there is a whistling sound coming from under the power distribution center (PDC) and a clicking that goes on and off for a bit. It feels like the relays are trying to engage but it goes from relay to relay and they are all good. With the error code of P0601 is it possible that the PCM needs to be replaced/reflashed in order to clear the code and get the engine to fire? Just a thought and a symptom that I have noticed.

 

I'm no mechanic so please don't take this to mean too much... but from all the threads I've read on here I think I would replace the PCM next.... Good Luck!

 

Ordered a new PCM. Will update with results later this week.

 

Where did you order the PCM from? Did they flash it with your current mileage and Vin Number?

 

Nick,
I ordered it thru autocomputerexchange.net
Yes they are flashing the rebuild PCM with my vin and current mileage. The cost was better than ordering a brand new one so hopefully this will fix my problem. I will update this thread once it arrives and is installed.
Randy