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Tach not working, causes??

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Old Apr 21, 2006 | 02:40 PM
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Default Tach not working, causes??

What could cause the tach not to work? It will intially move RIGHT when the car fires, then it goes to 0 and stays there. Is there some cable that runs to back of it or somewhere in the engine bay?

I'm trying to determine if it's directly related to my cam sensor issue on my LS2 402.

Thanks!
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Old Apr 21, 2006 | 04:37 PM
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Are you throwing any codes?
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Old Apr 21, 2006 | 05:20 PM
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Originally Posted by 99whitews6
Are you throwing any codes?
Cam position sensor Been trying to get that one settled for a couple days, still no luck
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Old Apr 21, 2006 | 05:38 PM
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So I would assume that you have removed the timing cover and verified that the cam retainer and cam bolts are tight and haven't backed out? Same thing happened to me before the engine went south. Cam bolts backed out and the cam lobe moved enough off center of the lifter and shredded a lifter.
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Old Apr 21, 2006 | 08:22 PM
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This has happened since first start up, and the motor has 15 miles on it, I doubt the cam bolts backed out on the first start up causing the no cam sensor problem. I'm going to buy another sensor and see if that works, then it will be another harness, then it will be something else, etc, etc. I will not tear into this motor.
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Old Apr 21, 2006 | 08:57 PM
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Originally Posted by Orange Peel
This has happened since first start up, and the motor has 15 miles on it, I doubt the cam bolts backed out on the first start up causing the no cam sensor problem. I'm going to buy another sensor and see if that works, then it will be another harness, then it will be something else, etc, etc. I will not tear into this motor.
Sounds like a plan Good luck!
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Old Apr 21, 2006 | 11:11 PM
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Thanks, it's not going to be fun!
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Old Apr 22, 2006 | 07:50 PM
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I just had this happen to me about a week ago. I had a low voltage-cam sensor code. Shortly after the tach went out, the SES light came on. I replaced the cam sensor, erased the code, and been golden since then. Good luck.
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Old Apr 22, 2006 | 08:32 PM
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Yeah the cam sensor is next on my list to replace. Thanks for the glimpse of hope
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Old Apr 25, 2006 | 07:53 PM
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I bought a new sensor today, replaced the sensor and STILL have no tach and the hard starting!!!!! I reversed the wires AGAIN back to the way it came on the male ended plug that goes into the sensor, STILL have no tach and still hard to start. I switched them BACK to the suggested swap way again and it's still the same.

My next step is to pull the harness and check it, but it's SUCH a pain in the *** to get to on the back of the intake area. What the hell is going on? Bad harness maybe??

Why me!!!!?
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Old Apr 25, 2006 | 09:03 PM
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bad computer?
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Old Apr 25, 2006 | 09:03 PM
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You could be crossing the incorrect wires. Which ones are you switching?
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Old Apr 25, 2006 | 11:34 PM
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the red and the brown, leaving the pink one in the middle alone. I'm only switching them on the end that plugs into the cam sensor, the end in the back by the head is untouched.
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