Chrysler Repair: Ignition sensor on late 80s 3.0L eng., crank shaft position sensor, crank sensor

Question
QUESTION: Mr Finston, My stepson has this vehicle & knows nothing about diagnosing problems. Someone told him he needed a crank sensor because of lack of fire. He went to a parts store where they sold him a sensor but said they knew nothing about it's location or how to replace it. He told me on the phone,(I do not live close) someone told him it was located on the transmission & there was more than one. Can you help please?????

ANSWER: Hi Larry,
There is one sensor with two wires and it is located in the distributor of the 3.0L engine. It is basically a cam sensor for that reason and there is not crank sensor at all. It is a round disc and he needs to remove several screws to reach it, all inside or associated with the distributor.
Before r&r of the disc, it would be good to validate that a code has been found in the memory of the engine controller that says one of the signals is missing. Turn the key:"on-off-on-off-on and leave on" doing that in 5 seconds or less elapased time. Then watch the check engine light, which remains "on", to begin to flash, pause, flash, etc. Count the number of flashes before each pause. Then repeat to be sure you get the same set of counts. Then group the counts in pairs in the order of appearance to form the two-digit fault code numbers. The last such number is always 55 which is the code for 'end of readout'. A code 11 or 54 is corroborative of a need to replace the photo-optic sensor.
Write back for the details of how to do that, if necessary. It could be something else, so get the codes first.
Roland

---------- FOLLOW-UP ----------

QUESTION: Thank You Roland, I'm sorry but I told you the van was a late 80s model. After speaking with him on the phone I was told it is a '98' model. Is the sensor still in the distributor???

Answer
Hi Larry,
No, there is also a crank shaft position sensor added to the engine since the 80's. The distributor cam sensor is still there, but was changed in its design. There is a separate fault code for each, and unfortunately you can't get the code of that year's model with the key but instead need a code reader. If he has a digital voltmeter he can check the signals from each to see which one may not show the proper signals. The crank sensor appears to be accessed from the under side of the engine where it looks at the flex plate between the engine and transmission.
Roland