Blue94Accord

Hey guys. So my efi ecu fuse keeps blowing. Trying to find out where the wire problem is. I changed my fuel pump to a walbro and I put the head back onto the block inside the car.

I checked a lot of things that could have blown it.(blows every time i turn the key on)
unplugged: alt, ecu, injectors, injector resistor, distributor. main relay.


now, if we unplug the wire harness right next to the fuse box, the fuse doesnt pop. using a test light touching the black wire connector that goes to the ecu it pops. black wires going to the ecu are a23 and a24 which are grounds.

im lost. thinking maybe its a wiring problem near the pump.. any ideasss im running out of fuses lol

soon2bdropped

if you unplug the harness where the fuse box is and it doesnt blow than you found your problem right there. look over the wire carefully..

Blue94Accord

its just a ground wire tho that goes to the ecu..

Blue94Accord

ok so update. I think that ground wire goes to the main relay.
Also, The 3rd wire on the main relay melted. I had smoke coming from inside the car and I found that that wire was the one melting. Its brown with a black stripe. Havent figured out what its for yet. I dont think the short is anywhere in the engine bay. Ive unpluged so many things and nothing effected it.
This is such a pain in my ***, I didnt even touch anything inside the car so i dont know what happened other then a fuel pump issue causing all this.

redbull-1

The brn/blk wire is an ECM/ECU wire. Normally, if the circuit has a fuse in-line, the fuse blows, otherwise the wiring overheats due to the short (e.g. ground is touching a positive wire or terminal).

Items to check or recheck.

Battery
Ignition Switch
Starter
ECM
Fuel Pump

Blue94Accord

Cool thats for the digram. Ill start checking those wiring in a little bit. Maybe its the starter or ignition

Blue94Accord

i tried unplugging the starter. nothing.

The only thing i have really checked was the fuel pump. I reached up in there and the wire harness feels fine but i can only feel a little bit of the harness.
The wire harness in the trunk, if i unplug that 3 wire plug, does that go to the fuel pump? Cause with it unplugged the fuse still pops. If its the power wire to the fuel pump wouldn't that mean the short is somewhere else and not by the tank?

I was looking at the wire that melted and i can see it melted all the way up under the dash. melted right through the electrical tape.

Blue94Accord

ok update,
I cut the brown with a black strip wire that goes to the main relay. The fuel pump pumps and the fuse doesn't blow. The problem now is the injectors aren't working. I sprayed brake cleaner into the TB and the motor fired and dies. So in short its getting spark and just the injectors aren't working now.

So, im not able to trace were that wire leads to cause is disappears into the dash so im going to go to the junk yard tomorrow and rip an accord apart and trace that wire.

Unless one of you guys know exactly..

redbull-1

As stated in my previous post, the brn/blk wire is an ECM/ECU wire. It's part of the the engine wire harness and then the main wire harness. One of the diagrams also shows the injectors and injector resistors in circuit with the ECU.

Blue94Accord

I cant see that one picture its to blurry. could you send me a better version to my email?

redbull-1

Check your pm.

Blue94Accord

ok cool, i printed out some diagrams from that manual. Looks like the brwn/blk wire goes to the ecu or data link. I remember checking the ecu wires tho and they all looked fine. Where exactly would the brown wire go to on the ecu?

I found another guy who had the same problem and it turned out for him that his exhaust melted his o2sensor wire and the 2 wires were touching causing his ecu fuse to blow. i remember checking mine tho so i dont think thats the case for me

Blue94Accord

I win. problem fixed. Turns out the iacv sensor was causing the short. The wires were grounding out on the firewall(skunk2 intake manifold in an accord is bad. The iacv is pinned against the firewall.

So the idle is a little bad the but it runs and I drove it home today. Thanks for the help guys