Chrysler Repair: 3.2L,/3.5L code 0340, crankshaft pulley, pulley bolt


Question
QUESTION: Engine is 3.2L, 200000 miles, check engine light came on,, don't remember code, but it said the cam sensor error, cleared the code, installed new sensor, check engine came back, 1-2 minutes, checked voltages to sensor (approx 5 volts) but no voltage going to PCM. same as old sensor. checked for shorts to ground, all OK.. checked wires to pcm, all OK...all the way to connector on pcm.. do not know what else to do...going to wait for your answer.. than to a mechanic... low in $$$$.... got a third sensor,, same...

ANSWER: Hi Pablo,
I assume that the original and the present fault code is shown to be an 0340, if not let me know.
Are you aware of the use of the 'paper spacer' on the tip of the new sensor? It is to allow you to put the sensor crystal very close to the surface of the camshaft sprocket but not to touch it, which would damage it. You are supposed to put the sensor in the hole until the paper covered tip is in contact with the metal surface, then secure it in that position. The subsequent rotation of the sprocket then rubs off the paper spacer but leave the sensor tip untouched and therefor undamaged.
As for the voltage not going to the pcm, the voltage signal is actually pulsing very rapidly between 5v and 0.3v and it won't be 'read' by a simple voltmeter. To verify that the sensor is good, you must turn the engine by hand using a socket and handle on the crankshaft pulley bolt.
So turn to the key to the run position and rotate the engine by hand to see whether or not you see pulsing 5 to 0.3v or not. If not, then if there is 5v on the violet/white wire either the sensor is bad or the signal wire (tan/yellow) is shorted to ground or the signal ground wire (black/light blue) is floating.
The only other possibility is that the timing belt broke but you would have heard that (interference noise).
So re-check the situation in light of the above information and let me know what you learn.
Please read the PS below and make a response to it.
Thanks,
Roland

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QUESTION: The new sensor (used but supposely good)did not have the spacer,, showed wear where the spacer goes.. Supply measured supply voltage,, 7.5 vdc,, signal measured 0.26 vdc (not 0.3-5.0 vdc you say). COULD SENSOR BE WEAK, GOING/GONE BAD, signal ground is not floating, 0 ohms to battery ground... and the code is 0340

ANSWER: If the voltage didn't oscillate between 5 and 0.27 while you were rotating the engine by hand then it would be a bad sensor; otherwise if it pulses back and forth it is good. If it was installed without the spacer it may have been damaged by rubbing the surface against the metal of the sprocket.
Please rate this answer and consider a 'nomination'.
Thanks,
Roland

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QUESTION: Looks like my sensor is bad, the wiring checks OK,,, one more final question,, the reading that I get, oscillates between, .26 and .11 vdc.. could it be that my sensor is too far out,, and I should put a new paper spacer to be accurate,  to see if I can get a higher signal reading to pcm,, going to turn engine to where the the reading is the highest and adjust the sensor to see if I get a higher reading... if no higher reading, then I will set the new sensor at same location, and should get a higher reading,, Right?

Answer
Hi Pablo,
That may be true if you rotate to the .26 location and you put it in further very slowly you will get 5v without it touching. So give that a try. If you get it, then rotate the crank more and see whether you then get 5-0.3V oscillation reliably or get a new spacer and try again. If  still not, then it would appear it is damaged beyond repositioning it.
Roland
PS I would appreciate your doing a rating and nomination of me. Click below to do that.