Author Topic: anyboby take apart magnetic  (Read 1625 times)

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cz777

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anyboby take apart magnetic
« on: March 01, 2013, 06:27:11 PM »
distributor ..looking under the magnetic pick up plate ....at the  mechanical  timing  slots one long [21] vs. short [18] <- mark with over slot  ...whats the use of this ??

Offline sharpxmen

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Re: anyboby take apart magnetic
« Reply #1 on: March 01, 2013, 06:32:47 PM »
the magnetic pickup in the AMC 2.5 and 4.0L YJ or TJ distributor (if that's the one you're asking about) is used for injector opening reference, not for ignition timing.

EDIT: i'm not sure what you mean by the long/short slots, there's a tone ring that passes in front of the cam sensor in the distributor, it's about 1/2 a circle
 - a picture could help, i can't visualize what you're asking but next time i'm in the garage i'll have a look at my spare to see if i can figure it out. It might be that we're talking about different models and not the MPFI one.
« Last Edit: March 01, 2013, 06:41:51 PM by sharpxmen »
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Offline Jeffy

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Re: anyboby take apart magnetic
« Reply #2 on: March 01, 2013, 08:19:36 PM »
the magnetic pickup in the AMC 2.5 and 4.0L YJ or TJ distributor (if that's the one you're asking about) is used for injector opening reference, not for ignition timing.

EDIT: i'm not sure what you mean by the long/short slots, there's a tone ring that passes in front of the cam sensor in the distributor, it's about 1/2 a circle
 - a picture could help, i can't visualize what you're asking but next time i'm in the garage i'll have a look at my spare to see if i can figure it out. It might be that we're talking about different models and not the MPFI one.
He's referring to the tone ring.
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Offline sharpxmen

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Re: anyboby take apart magnetic
« Reply #3 on: March 01, 2013, 09:20:42 PM »
the tone ring disrupts the magnetic field and causes the signal to be generated in the CPS (camshaft position sensor), that's all it does. it works like this: the PCM receives the signal and uses that to set the injector opening sequence (where inj #1 will open and the others in the same order as the intake valves  open after that, that's why is called cam position sensor).
'95 YJ, NSG370 6spd / Hurst shifter, Dana 300 + 4:1 Doubler / tri-stick, Custom skid, Super D35 / Auburn LSD / 4.88, 35x12.5x15 BFG KM2, 64mm t/b, 1.7 RollerRockers, MkVIII e-fan, Dual Diaph Booster
Latest: Corbeau BajaRS heated seats :dance: keeping warm the rear end