Engine turns over but doesn't start

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mark D

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I have just bought a 1996 Discovery SE; 4.0 gem engine, automatic transmission.
I bought it from a women that was tired of mechanics charging her and not fixing the vehicle. It transported soccer kids around its entire life and shows no off road use at all.

Long story short: The previous owner was told by her mechanic the ECU was cooked, so she bought a used one on line and had him install it, after installing the used ECU (bad idea) it still didn't start. She sat on it for a few months and then she sold it to me.

First I reinstalled the original ECU to see if I could read the codes (no codes most likely cleared by the mechanic). I left it in to see if it was working all along and started my own diagnostic.
Second I bought a new crank positioning sensor and in the process of installing it, I found the sensor wires were cracked and in contact with each other about 6" from the plug up.

Question Before I scuff my knuckles up and get grease buried in my finger nails. Is there a way this condition could fry the ECU? Should I install the sensor loosely just to see if I can get the rig to fire? (I know it takes three arms and a lot of patience to install the sensor and cover, a real pain)

I am thinking I should replace the wire back to a location it is not fragile and install the new crank positioning sensor, and give it a try. But I want to know if it could burn the ECU out????

Has anyone seen this before?

BTW IS this 96 GEM worth fixing up for a camping or a rock crawler????? Its straight except for the headliner? I know there are a lot of bad opinions about GEMs I know they are the same block as the Bosh, but I just wanted some input.

Thanks
Thanks
 
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mark D

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Ok replaced the CPS, rewired the plug, (Just checking the on the 1996 there are only 2 wires going to the CPS not three as described in the later models?) Also the wire mesh wrapped around the sensor wires was for heat protection is assume????

I found a brown wire and a green wire; both heat rotted and touching together all the way up to the intake manifold.

I removed the plug soldered 2 new 18 gauge wires in place of the old ones using the old plug connectors and made an aluminum conduit up past the exhaust manifold to sleeve the wires and help protect them from heat in the future.

Still not starting. Do I have to reboot the ECU to get it to fire???
 

mark D

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CPS no spark

I have changed the CPS and CPS wire, reinstalled the unit and still no spark

Things checked so far.

*New CPS
*New CPS wire checked contanuity its good
*Fuel pressure is good
*Battery is charged
*Did a hard boot on the ECU by connecting the positive and negative battery cables together for 20 mins.
*Cleared alarm imobilizer
*checked inertia switch
*checked trans switch cranks in P and N but not in D
*checked coils no spark
*checked all fuses
*checked all relays

Discovery was running fine before it stopped.

what next????? Please.
 

mark D

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CPS no spark grounding

Does the CPS need to be grounded to the frame? if the CPS is not making full contact with the engine ground does it fail to conduct the 5 volt current that signals the ECU to time the spark?

How much voltage should I see if I test the wires with a volt meter if I turn the engine over with a voltage tester attached to the sending wires?
 

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