Serious wiring problem

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ZootedS13
Posts: 296
Joined: Fri Sep 11, 2009 8:51 am
Car: 1990 240sx se

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i swapped in my sr20det in my 240sx and im having some wiring issues. i followed the frsport wiring guide and did everything exactly like they said. i was testing for power in my coil harness and i only get the far right pin to give power(i believe is the signal wire?). the same thing was happening with my tps. then i found a ground that wasnt being connected so i grounded it. the signal that i was getting from the tps and coilpack harness is gone but theres still no main power to any of them (im not even sure there is supposed to be ) the main problem is im not getting spark at all, iv changed plugs all coils and i just cant get spark. could this be a ground problem? a relay problem? im not a wiring guru in the least.


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OM3GA
Posts: 3041
Joined: Fri Apr 14, 2006 11:41 pm
Car: A Sexy Mobile, 1993 Nissan 240sx 180sx Hatcher

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Interesting, sounds like it needs to be really tested.

I cant really figure it out just from how it sounds but if you get really tired of dealing with shoot me an email.

The key is in the on position while you are checking this stuff correct?

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ZootedS13
Posts: 296
Joined: Fri Sep 11, 2009 8:51 am
Car: 1990 240sx se

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yes, key is on position when i test everything. there are so many variables that change what prong is getting power on each plug.

ill try to be more specific.

when those tiny grounds that bolt to the manifold are grounded

tps-no main power, no signaleach ignition coil plug- no main power, no signalcas-main power, but no signal

when those two tiny grounds arent grounded

tps- getting signal, no main powereach coil plug- getting signal, no main powercas- getting signal and main power

but there are other variables such as if the cas is plugged in or not and some plug on my body harness in my engine bay that is looped back to itself for some reason. im pretty sure iv tryed every combination of switching up wether the grounds are grounded or not, not looping that plug in my body harness and plugging in the cas.

no matter what i try i have yet to see main power to the coils whatsoever. i cant believe this stupid wiring is the only thing holding me up from driving this beast.

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Wiring Specialties
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Joined: Mon Apr 11, 2005 5:04 pm

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I assume this is a S13 to S13 swap?

If so, most of the power comes from the chassis, by the passenger headlight. You have to simply match the colors of the wires when you ar ereplacing or repinning the plugs in the grey and copper color connectors.

MAFS, CAS and Switched ECU power all come from the black/white wire by the headlight.The coilpacks are powered (should be) by the blue/red wire, which you shoudl jump to the thick black/red.Injectors have a constant feed by the red wire, also located by the headlight. The TPS is powered by the ECU with a 5v signal. Green/red wire.

It is possible there is a short somewhere, as there should be no change in the signal when you are grounding something.

You hav eto take 1 issue and find a solution to it, then move on to the next. Otherwise you will have a tough time getting this thing running.

p.s. Make sure you did not connect the O2 connector to the Temp sensor connector by the Trottle body.

Good luck and let us know how it goes.

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ZootedS13
Posts: 296
Joined: Fri Sep 11, 2009 8:51 am
Car: 1990 240sx se

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yes s13 to s13. im going to open up my harness and see if the blue/red is jumped to the main ignition power. my friend and i did my hanress but to be honest im very colorblind. looking at a mesh of wires sometimes make them all the same color!

what blue/red wire on the sr harness goes to the main ignition power from the ka clip?? theres a very small one and a thick one?
Modified by ZootedS13 at 10:41 AM 2/9/2010

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Wiring Specialties
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Posts: 494
Joined: Mon Apr 11, 2005 5:04 pm

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No need to open the harness up. Just look at the location you were working on. most likely its 6-10 inches away from the power plugs by the headlight.

To power the injectors you have to power the thick blue/red wire from the thick black/red wire, so y ou have a 1 into 2 connection.

This is as basic as it gets with dozens of diagrams available.Have a look and let me know. DO NOT take the harness apart as it will cause issues and potential damage later with moisture and corrosion.

ThanksYury

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ZootedS13
Posts: 296
Joined: Fri Sep 11, 2009 8:51 am
Car: 1990 240sx se

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thankyou guys, i took out the harness and redid all the solders, turns out the blue/red wire wasnt making the connection well enough. i put the hanress back in and it started right up!

my guauge cluster isnt working tho, not sure if i need a dohc one or not. and the eninge idles Very high. ill search for all that stuff.

thanks again!

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homeslicej2
Posts: 5446
Joined: Mon Jan 15, 2007 5:46 pm
Car: 1990 Nissan 240SX S13 SR'd hatch

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ZootedS13 wrote:my guauge cluster isnt working tho, not sure if i need a dohc one or not. and the eninge idles Very high. ill search for all that stuff.

thanks again!
If it's wired correctly, your gauge cluster should work except for the tachometer (if you put the KA speed sensor into the SR transmission that is). Double check your dash plug wiring. The SOHC tach can't read the RPM's at all. You'll need to swap in an S13 DOHC or S13 SR tach for it to work. Pulling the cluster and installing the tach is easy. You might have an incorrectly adjusted TPS causing your high idle.


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