Just wired LS2 coils, no power to ecu/fuel pump prime

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tuzzio
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Just wired LS2 coils, no power to ecu/fuel pump prime

Post by tuzzio »

Okay guys. Just finished up wiring my ls2 coils. Went to plug in my laptop to change the settings in my aem and it won't connect or notice the usb cable, and my fuel pump doesn't prime, it did before this and the laptop has been plugged into the car numerous times. I used the diagram from aem's website. Its an s13 ka. http://aemelectronics.com/files/instruc ... %20EMS.pdf

Coil triggers:

Coil 1: #1
Coil 2 is #7
Coil 3 is #5
Coil 4: is #25
I used #21 for the ecu ground (sensor ground)
One ground running to the head
And the power is pin #36 which was previously running to a relay for the Hotwire mod
So what gives? What did I miss?

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superDorifto
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Re: Just wired LS2 coils, no power to ecu/fuel pump prime

Post by superDorifto »

Not sure that it matters, but Im pretty sure the ecu is not capable of powering the coils.

For mine, we had the 4 triggers pinned back to the specific pin on the ecu. A dedicated fused hot wire run in parallel for power that did not go through the ecu.

For the power ground we again ran all the grounds in parallel back to one of the sensor grounds. The signal ground we ran in parallel to a valve cover bolt.

Also used shielded wire fire the power and signal.
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BigLoukaT
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Re: Just wired LS2 coils, no power to ecu/fuel pump prime

Post by BigLoukaT »

Super... Are you mixing up your ground paths?
I'd expect power ground going to engine metal, and signal ground going back to ecu?
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tuzzio
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Re: Just wired LS2 coils, no power to ecu/fuel pump prime

Post by tuzzio »

I don't believe so. I assumed the same, but a few links online stated that people running ls coils on aem standalones used sensor grounds. So thats what i did, I believe this ground also has my iat/map sensor grounded to it as well.

Pulled all fuses, nothing. No broken fuseable links. I'm really confused.
tuzzio
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Re: Just wired LS2 coils, no power to ecu/fuel pump prime

Post by tuzzio »

Just did some digging.

Pin #36 needs to be connected for whatever reason, snipped and twisted them together, and now the fuel pump primes. Going to plug my laptop in and see what happens. If it has power, i'll take my power source for the coils from elsewhere.
tuzzio
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Re: Just wired LS2 coils, no power to ecu/fuel pump prime

Post by tuzzio »

Anyways, Seems like for whatever reason, pin 36 needs to stay connected to factory settings.

Used pin 28 for power and changed it in the standalone to 12v switched. Now the problem i'm running into is that I have no spark. I have power to the coils, but doesn't seem like its getting signal while cranking.
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Re: Just wired LS2 coils, no power to ecu/fuel pump prime

Post by ViperGT »

you figure it out? LS coils are either 4 pin or 3 pin im not sure but its all the same. 1 pin (power 12v) gets 12v switched or continous 12v doesnt matter, through a fuse to the battery or fuse box whatever, this will need to be like a 14g wire or thicker(high current pull cant go through ecu), then there will be another pin (power ground 0v) that needs a high current ground, this needs a 14g or thicker wire to a solid ground, either back to battery or a nice bolt on engine/ firewall, then there will be the trigger (ecu switched 5v) and this will run to the respectable pins on the ecu for each coil, this wire can be thin 18g-24g, the last wire is the sensor ground this can be also a smaller wire and run this to sensor ground on ecu. the two big wires will be on the out side and the 2 smaller ones in the middle. see this link for exact placement, http://www.megamanual.com/seq/coils.htm as for ecu settings i cant say and im too busy drawing up a new harness for my car to look for ecu pins and triggers, ran this post over looking for the wiring to the dizzy, cant remeber if it gets 12v or 5v LOL. still need to get my truck coils on my car,
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tuzzio
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Re: Just wired LS2 coils, no power to ecu/fuel pump prime

Post by tuzzio »

Alright guys, i'm back at it again. The last time it seemed that my issue was in my plug wires, so I had magnacore make me some wires and now i'm trying to figure everything out. Got everything wired up, power to all coils (checked with a test light)

Went into AEM (v2 30-6600) and used the coil wizard to change the settings to LS2 coils (using 12573190)

Went to the coils/inj table, and switched coils 2,3,4 to on. What should the phasing be?

If anybody has a map running LS coils on there s13 ka, it would be great for some help/email me your map.
tuzzio
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Re: Just wired LS2 coils, no power to ecu/fuel pump prime

Post by tuzzio »

I was using the settings that were on the first page in this:viewtopic.php?t=26234 thread. Here are my current settings, car still won't start.

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What am I missing?
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Re: Just wired LS2 coils, no power to ecu/fuel pump prime

Post by sdaigle240 »

eye heart tuzzio
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Re: Just wired LS2 coils, no power to ecu/fuel pump prime

Post by tuzzio »

I <3 daigle.
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