S14 EGI Fuse keeps blowing?? HELP!

[JohnnySRZenki]

Hey guys, i've been going crazy trying to find the problem for my s14, which i cant. I've done loads of research, but i have yet to find the solution. Here's the situation. I have a s14 with the following mods:
s13 sr20det black top
255 Walbro
Electric fans
Wiring specialties s13 to s14 wiring harness
Thats all, no much.
Nowww to the problem, IT KEEPS BLOWING THE DARN EGI 7.5A FUSE
We replaced it, started right up, then 10 miles down the road, it shots a flame, and the car dies. It also fried my ecu once, which wasn't cheap to replace.
The car wont start, cranks, with spark and fuel, but wont turn over. I've checked the grounds and it's all fine. Also, the blue relay that's near the ecu also makes a ticking noise (the f2 plug i think ecu or fuel pump)
Anyone?

[Ken@PTUNING]

Sounds like you've got a short. You'll want to trace the harness for any possible spots the wiring could be shorting out. Try doing continuity tests between the chassis and the ECU's power wires. The ticking noise is likely the relay being switched on and off intermittently.

[PapaSmurf2k3]

^Agreed.
The only other thing I would suggest would be to try to monitor amperage draw through that circuit. If you're super close to 7.5A all the time, you might have something simply drawing too much (a sensor or something) - in which case hunting a short would be barking up the wrong tree.

[Ken@PTUNING]

^Agreed.
The only other thing I would suggest would be to try to monitor amperage draw through that circuit. If you're super close to 7.5A all the time, you might have something simply drawing too much (a sensor or something) - in which case hunting a short would be barking up the wrong tree.

That's a good point.

@JohnnySRZenki
Do you have any gauges hooked up to that circuit? What about any other aftermarket electrical accessories?

You mentioned you fried an ECU once before. Was it a related issue?

[essfourteen]

Also remember that Yuri at Wiring Specialties gives 24/7 tech support on his harnesses. If you think its an issue with the conversion harness, shoot them an email or give them a call. They're EXTREMELY knowledgeable about S chassis wiring and can probably tell you right away what the issue is.

[JohnnySRZenki]

Also remember that Yuri at Wiring Specialties gives 24/7 tech support on his harnesses. If you think its an issue with the conversion harness, shoot them an email or give them a call. They're EXTREMELY knowledgeable about S chassis wiring and can probably tell you right away what the issue is.

That's what i thought, but they're so hard to get in touch with, and everytime i call, They all seem to be in a "meeting"

[JohnnySRZenki]

^Agreed.
The only other thing I would suggest would be to try to monitor amperage draw through that circuit. If you're super close to 7.5A all the time, you might have something simply drawing too much (a sensor or something) - in which case hunting a short would be barking up the wrong tree.

That's a good point.

@JohnnySRZenki
Do you have any gauges hooked up to that circuit? What about any other aftermarket electrical accessories?

You mentioned you fried an ECU once before. Was it a related issue?

Sorry for the late reply, The mobile version sucks. I Have nothing connected to that circuit. The only aftermarket electronics would be my Radio, Boost gauge (Which only needs power to light up) and my highbeams are wired to a switch.
I think it was. After opeing the ECU, the circuit for my fuel pump relay or fuel injector number for was burnt out. The wires has also melted for the relay that was clicking. But i figured it was because i decieded it would be a great idea to add a bigger fuse.

I also forgot to mention that the car was running perfect for a year. This started out of no where. I need to put my engine harness back in, i will keep everyone updated with what's happing! Thank you for your replies!

[Ken@PTUNING]

The short will very likely be on the circuit related to the melted wire. Trace the section of the harness that the melted wire is located in. Check all sections that have melted. Replace the melted wires as uninsulated wiring is a huge fire hazard. Check for sharp edges the harness may be making contact with such has chassis pinch welds, bulkhead holes, etc. Vibration in the engine bay over time can cause wires or insulation to be cut.

[JohnnySRZenki]

The short will very likely be on the circuit related to the melted wire. Trace the section of the harness that the melted wire is located in. Check all sections that have melted. Replace the melted wires as uninsulated wiring is a huge fire hazard. Check for sharp edges the harness may be making contact with such has chassis pinch welds, bulkhead holes, etc. Vibration in the engine bay over time can cause wires or insulation to be cut.

I guess solid mounts wouldn't help haha. I'll pull up a fsm and see if I could trace it back.

[JohnnySRZenki]

The short will very likely be on the circuit related to the melted wire. Trace the section of the harness that the melted wire is located in. Check all sections that have melted. Replace the melted wires as uninsulated wiring is a huge fire hazard. Check for sharp edges the harness may be making contact with such has chassis pinch welds, bulkhead holes, etc. Vibration in the engine bay over time can cause wires or insulation to be cut.

Just checked it, seems to be my ECCS Relay that had melted wires. It's also sending a positive feed through the ground. Has to be a short. But does this mean it's on the engine harness i bought? Or could it be a chassis wiring problem?

[Ken@PTUNING]

A bad relay doesn't normally cause a short like that. All a relay does is complete a circuit. Whether that circuit is a short depends if the circuit is completed with no load/resistance. If a relay completes a shorted circuit, both the wiring and relay may fail because it will allow for unimpeded current flow, causing the heat that melted the wire.

Normally, the ECCS relay powers the CAS, MAF sensor, the ignition coil relay, and the ECU. Check them out and see if you find anything. Diagram below for reference:

http://www.nicoclub.com/articles/images ... iagram.gif

[essfourteen]

Trace the melted wires back to where ever they come from. You'll likely find a portion of that wire grounded to the chassis.

[JohnnySRZenki]

A bad relay doesn't normally cause a short like that. All a relay does is complete a circuit. Whether that circuit is a short depends if the circuit is completed with no load/resistance. If a relay completes a shorted circuit, both the wiring and relay may fail because it will allow for unimpeded current flow, causing the heat that melted the wire.

Normally, the ECCS relay powers the CAS, MAF sensor, the ignition coil relay, and the ECU. Check them out and see if you find anything. Diagram below for reference:

http://www.nicoclub.com/articles/images ... iagram.gif

Pin 112 On my ecu was fried. (On the board itself) Which traces back to the Fuel injectors and Coil packs. Could it possibly be a bad coil, and/or injector? I'll trace the wires once i am off of work.
(FYI if you couldn't tell im not very advanced with cars)

[Ken@PTUNING]

An injector only fires when the ECU grounds out the circuit. A bad injector won't create a short. That pin should be the main power circuit for the ECU. A short there would fry it.

(Don't worry, nobody likes electrical issues.)

[JohnnySRZenki]

An injector only fires when the ECU grounds out the circuit. A bad injector won't create a short. That pin should be the main power circuit for the ECU. A short there would fry it.

(Don't worry, nobody likes electrical issues.)

I'm on the merge of selling this car. Or trading it for a motorcycle. Anyone? Lol. So my only bet right now is to trace the wires back?

[Ken@PTUNING]

Yes.

[Ken@PTUNING]

Like I mentioned before, you don't necessarily need to rip the harness apart and trace the wiring. Check the wires that lead to the sensors mentioned above. Check their junctions, any sharp turns, or where it may come in contact with the chassis. Check the connectors for any cut/exposed wiring.

[JohnnySRZenki]

Yes.

Thanks for the instant replies man. I really appreciate it.
Thanks to everyone else too. I'll keep you all updated.

[JohnnySRZenki]

An injector only fires when the ECU grounds out the circuit. A bad injector won't create a short. That pin should be the main power circuit for the ECU. A short there would fry it.

(Don't worry, nobody likes electrical issues.)

After 3 hours of ripping this s*** apart I think I finally found the wire. I tracked back the wire that was melting and found the smallest slice into the wire. (Look at the pic, you could see it burnt too) so I'm still trying to figure out what wire it was exactly, but I'm 90% sure it was my MAF ground.

[Ken@PTUNING]

Nice find! It's always a pain but hopefully now you can enjoy the car again!

[essfourteen]

Boom. Profit.