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Cam position sensor

ruffin1ruffin1 Member Posts: 2
edited October 2015 in Chrysler
I installed a new cam position sensor following instructions in Hayne's manual, seated it down on the paper spacer, but when I run car it is idling at 1500rpm, very rough. I found that if I break loose the sensor and raise it up about 1/8 of an inch while the car is running the idle smooth's out to 500rpm and runs great, but when I stop car and restart I have to repeat this procedure, putting it back down in order for the car to start and raising it again to smooth out the idle. I put old cam sensor back in and found it doing the same thing. why would this occur??


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    thecardoc3thecardoc3 Member Posts: 5,772
    edited October 2015
    You would be most likely changing the phasing of the camshaft signal as compared to the crankshaft signal when you move the sensor. With a digital oscilloscope we would capture some waveforms for direct comparison to known good waveforms in order to measure how much variation is occurring. What we would need to see would be both a compression waveform using a pressure transducer, and the camshaft and crankshaft signals so that they can be compared to known good captures. You cold easily have a timing chain (belt?) issue or a broken flex-plate. (flywheel) There are some instances where the pick-up magnet that attaches to the camshaft comes loose or fails, and that is usually visible in the distortions that occur in the camshaft signal.
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    ruffin1ruffin1 Member Posts: 2
    Here's the story: My water pump locked up and my tensioner pulley blew apart. I replaced the pump and pulley and timing belt. My timing marks are all lined up, but this is the issue I've been having with it. I do have a trouble code 1391 I believe, which tells me that I have an intermittent signal from either the cam or crank sensor, but I can't get that belt adjusted more perfectly on the timing marks than it is. I'm actually driving it too, once I adjust the sensor it rums like a top.
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