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Eccentric Shaft Sensor wiring

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Old Aug 27, 2022 | 08:11 AM
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Eccentric Shaft Sensor wiring

Long story short,

The wiring for the eccentric shaft melted somehow. I cut off the area that was melted and replaced it with a new connector.

New connector did not come with shielded wiring, only the two wire leads, and now I'm having a crank no start issue with persistent code for the ESS. I coated the ends with some silver solder and then used 24 gauge butt connectors for the two lead wires, but I wasn't sure how important the shielding is.

Update: 01/02/2023 - After trying two ESS and a completely new engine harness, I'm still getting the error code for the ESS data after remounting. It's not getting spark from the coil, it's cranking at about 250 rpms with a fully charged battery. I tested for spark by running a test light from the 1st coil to the negative battery terminal. Any more suggestions? Made sure all the grounds were good, checks all the fuses in the fuse box.

Last edited by Dravethe; Jan 2, 2023 at 12:40 PM.
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Old Aug 27, 2022 | 06:18 PM
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Update
So I have a weird problem, when the ESS is bolted onto the engine on it's mount, the ECU acts like it's not getting any data and will not produce spark.

I then unbolted the ESS and placed in proximity to the ES, slightly closer than it's mounting bracket, and the ECU produces spark.

I've tried everything reset the ESS, difference EES, redid the wiring harness and shielding.
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Old Aug 27, 2022 | 11:09 PM
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From: Smallville
Try another sensor.
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Old Aug 28, 2022 | 09:40 AM
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Yes, I've tried two different sensors. They both do the same thing.
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Old Aug 28, 2022 | 10:31 AM
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If you have access to an oscilloscope then that's what would usually happen next....

how did you repair the harness? Shielded wiring is much more difficult to fix than regular wires. The shield needs to be grounded at the ecu end and have an uninterrupted path. The low output of the sensor also requires careful wire choices to prevent loss that will basically make the sensor stop working.
needing the sensor closer to the wheel leans toward loss of signal in the wiring.

Trigger wiring can be complicated as well.... if you route it too close to the alternator or coils it will pickup noise... even with the shield. So stock location is important
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Old Aug 28, 2022 | 12:07 PM
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there may be a wire issue further back than you replaced.

the 2-wire is sold out, but you can ignore/not use the 3rd wire on this 3-wire shielded wiring @ $1.00/foot

https://www.bmotorsports.com/shop/pr...g586nf0bue3a86

.
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Old Sep 8, 2022 | 10:27 AM
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Originally Posted by dannobre
If you have access to an oscilloscope then that's what would usually happen next....

how did you repair the harness? Shielded wiring is much more difficult to fix than regular wires. The shield needs to be grounded at the ecu end and have an uninterrupted path. The low output of the sensor also requires careful wire choices to prevent loss that will basically make the sensor stop working.
needing the sensor closer to the wheel leans toward loss of signal in the wiring.

Trigger wiring can be complicated as well.... if you route it too close to the alternator or coils it will pickup noise... even with the shield. So stock location is important
Thanks for the replies guys. I salvaged the chopper woven shielding from some coaxial cable, made sure to keep it's helical shape, and slid it down the wires for the new connector. I used a similar butt connector to attach it to the existing shielding, and wrapped the whole thing in electrical tape pretty good; however, it still didn't work. I just opted to buy a new (used) engine harness, but haven't been able to find a good one on ebay yet.

While I was taking off the old harness, I came across two of the grounding bolts, on the metal bracket the harness attaches onto, to be pretty lose to the point I could take them out by hand. It might have been the problem the whole time who knows. Anyways, I'm not going to waste the time of putting everything back together without finding a decent used one. I'll let you guys know how it goes.

Edit: Anything I should address while I have the UIM and etc off?
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Old Sep 9, 2022 | 05:59 AM
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From: In the 8
While your in there check and clean all ground connections. Then I would try it with the same harness.
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Old Sep 11, 2022 | 10:19 AM
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Originally Posted by Red line envy
While your in there check and clean all ground connections. Then I would try it with the same harness.
I would except I went kind of nuclear trying to get the injector plugs off. They aren't easy to get off with the engine still in the bay. Plus the UIM is enough of a bitch to get back on/off, for it still to not work, and in the event it still doesn't work the plastic is getting old. It's difficult to know when something is going to break just trying to remove it.
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Old Jan 2, 2023 | 12:40 PM
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bump
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Old Jan 11, 2023 | 12:23 AM
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it’s time to stop guessing and start troubleshooting

then the first thing to check is whether it’s generating a signal to the pcm during cranking



from there you need to confirm if a signal is being sent to the ignition coils




and then whether the coil itself is sending a spark


because potentially it grounded and burnt up the pcm circuit, or the coils, etc. etc.

which you never really explained or provided any insight on how it might have “melted”.
.
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