Jeep Grand Cherokee 3.7 Crank/Cam Waveform

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r3s1s74nc3
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Jeep Grand Cherokee 3.7 Crank/Cam Waveform

Post by r3s1s74nc3 » Fri May 17, 2019 5:39 pm

I'm trying to sort a problem with Jeep Grand Cherokee 3.7 V6 , 2006 . It setting camshaft sensor fault on bank 1 . Today I checked it , everything seems fine . 5V present , good ground , good sensor signal 0-5 V square waveform , but still the code is present . The car hesitat when you go on full throttle . So decided to capture crank / cam waveform to see is everything OK , but I'm not able to find known good one . If anybody can help me find one , will be highly appreciate :)

r3s1s74nc3
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Re: Jeep Grand Cherokee 3.7 Crank/Cam Waveform

Post by r3s1s74nc3 » Mon May 20, 2019 5:57 am

Guess I'm going to need to open the timing covers then :(

Martyn
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Re: Jeep Grand Cherokee 3.7 Crank/Cam Waveform

Post by Martyn » Wed May 22, 2019 5:58 am

Why not post your captures :)
Martyn
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r3s1s74nc3
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Re: Jeep Grand Cherokee 3.7 Crank/Cam Waveform

Post by r3s1s74nc3 » Fri May 24, 2019 4:16 pm

This is the capture of crank and the fault code camshaft sensor .
Attachments
Jeep 3.7 pic1.jpg

liviu2004
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Re: Jeep Grand Cherokee 3.7 Crank/Cam Waveform

Post by liviu2004 » Sat May 25, 2019 8:05 pm

There is one waveform in the library from a Jeep Liberty 2005 3.7 automatic.
Notes are: scantool show a 5 degree varience sensor have a good 0-5 volt square wave.
Test conditions: Key on Engine Running Idle.

Good news: cranks sensor waveform is the same.
Bad news: your cam sensor waveform is waaay different. You have big, small, medium, big, medium, if that makes sense. Library waveform has: three small, pause two small, pause, one small, pause three small, pause, one small, pause, two small.

So, are these engines cam sprokets different, or what?

Watch this 2008 cam pulse wheel, looks like on library waveform.
PIC_0707.jpg
Attachments
25811280-lb3yimx2pwhstnjl4tgwffiq-2-0.jpg

vasek
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Re: Jeep Grand Cherokee 3.7 Crank/Cam Waveform

Post by vasek » Sat May 25, 2019 9:05 pm

It's a V6 engine.
It seems that the camshaft sensor is faulty.
Synchronization should rather look like this.
Attachments
DODGE CARAVAN 3.3 V6 2008.PNG

liviu2004
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Re: Jeep Grand Cherokee 3.7 Crank/Cam Waveform

Post by liviu2004 » Sun May 26, 2019 5:16 am

And where is that different to what I’ve wrote?

vasek
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Re: Jeep Grand Cherokee 3.7 Crank/Cam Waveform

Post by vasek » Sun May 26, 2019 7:43 am

The author of the post asked to show - how to be the sync on the engine V6 ( CHRYSLER-DODGE-JEEP).
All NGC engines have the same synchronization.
This synchronization looks like on the screenshot.
Nothing else.
In the case under consideration,most likely, - there is no different cam sproket.
There is a faulty sensor, that reads a burst of pulses as one pulse.
That's all that was said.
Last edited by vasek on Sun May 26, 2019 8:25 am, edited 2 times in total.

vasek
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Re: Jeep Grand Cherokee 3.7 Crank/Cam Waveform

Post by vasek » Sun May 26, 2019 7:50 am

When the sensor is demagnetized,it starts to work this way.
Attachments
V6 NGC BAD CAM SENSOR.png

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