Beater EG

First off I have used the search engine to look for similar issues, I have noticed similar issues but the symptoms are different than mine.

I just bought this civic (my first honda) and have worked on others before. Here's what happens, as soon as I hook up a battery (in this case battery was dead was using my shops jumper pack) the ACG fuse blows. Car will crank all day long with no issues aside from no spark or fuel. Now this car wasnt at my shop and still isnt at the moment so I had very limited tools to use. I made a jumper wire with two spade connectors to jump eliminate the fuse just to see what would happen. Turned the pack on again, tried to crank and my jumper pack has built in voltmeter and instantly sucked it down to 4v and wouldnt crank, unplug the wire and it cranks fine at 10v or so, but still no fuel or spark.

Previous owner wired in a cheap sunpro tach and hacked a stereo in with wires running everywhere, I cut all the unnecesarry wires, he wired the cooling fan to a switch, also cut those to just because I dont know where he tapped in for power. Also previous owner put in new distributor, cap and rotor, starter, and fuel pump to fix this issue. When I got it the ECM was blown, pulled the top cover off and smelled horrid and a transisor exploded. I took a chance and plugged in a known good ECM from an automatic car with the 1.5 and was told by a number of my honda friends that it should work I just may have a CEL which didnt matter to me. Still same thing, crank no start, no spark or fuel. ECM made it out alive by the way.

Up by the distributor there is a black wire with yellow stripe that appears to have been cut from the connector and looped back into the distributor wiring via a butt connector (he says the guy before him did that). I havent pulled wiring diagrams yet and like I said I did search but the symptoms aren't the same in the threads I have read, and judging by some of the sketchy wiriing I've seen on it I'd say someone screwed something up. Obviously there is a short somewhere since the fuse pops the instant it sees any power.

Now my thought is I may just replace the whole engine harness to eliminate afore mentioned sketchy wiring. What I'd like to know (and believe me I'm open to any advice as I usually work on european cars) is what can could that much of a load that would stop it from even cranking when the connection is made? Is there anything that commonly triggers this sort of symptom? Am I right to just replace the harness right away? Or once up in the air and back at my shop would this be a pretty obvious flaw in the wiring?

This car is a $600 beater so I'm not against cutting a few corners, it's just gonna be a daily driver to get me from A to B, so keep that in mind as I dont want to put much money into it.

Beater EG

Anybody?

Former User

Does unplugging the IACV, alternator, and main relay prevent 15A dash fuse 24 (ACG) from blowing when the key is turned to ON(II)?

Or does fuse 24 blow even with the key in off?

Beater EG

Haven't had a chance to try that, didnt have the tools, will try that as soon as its back, a couple other people mentioned that. Appreciate the input and will keep updated if it fixes the problem out not.

Beater EG

Picking car up on saturday and bringing back to my shop, should have an update late saturday evening or sunday

Beater EG

Alright got the car, yesterday did a quick few simple tests. First i took off main power wire to alternator and unplugged the plug in the back, put in a new 15amp fuse in #24 and cranked away, cranked great, but no fuel or spark and the fuse was good.

Second test I plugged it back it but left the power cable disconnected, turn the key to on and the fuse blows right away.

I'm out at the shop today with a power probe and wiring diagrams but I've never used a power probe and I am admittedly not the greatest with electrical repairs. Any suggestions?

Beater EG

Started tracing the black and yellow wire, testing it at the fuse block, tested fuel pump just to make sure it worked at it did, tested at alternator and it tripped the breaker.

Tested it under the dash near the fuse box and firewall and it tripped the breaker. I followed the harness into the engine bay behind the drivers side strut tower and unplugged it from the connectors mounted behind strut tower. Tested the wiring going down into the alternator and it did not trip so I am assuming the wiring to the engine is good. I tested the wiring going into the body and the breaker tripped. Now I am assuming the wiring to the body may have a flaw in it either corroded or rubbed through but I tested very close to the firewall at the backside of the two large connectors going from fuse box into firewall leading me to believe that the problem has to be between those two points.

If anyone has any suggestions or has seen this before and was something totally unrelated please let me know.

Beater EG

Just unplugged the gray connector coming from fuse box going out to firewall. I tested connection going out and the power probe sent the power just fine without tripping the breaker, tested the other side of the connector and the breaker tripped. I have the large plug unplugged from top of dash fuse box where I tested the black and yellow wire and circuit breaker tripped. In this section of the harness I havent seen any sketchy wiring so at this point I think I have to start cutting away the plastic conduit and checking to see if the wire is broken anywhere or crossed with something else.

Again any suggestions?

Former User

What specific test are you doing when you say it "tripped the breaker"? Please give details.

Beater EG

I'm using a power probe to send 12v into the circuit trying to find the short, the power probe has a built in circuit breaker. I followed the black and yellow wire into a large portion of wiring harness that runs across drivers side into passenger side and out into engine bay on passenger side. I removed battery and battery tray, unbolted under hood fuse box and removed conduit and electrical tape and found a wire thats burned off all its insulation, obviously this is a problem, but this wire is white with green stripe, trying to pinpoint where this goes and also found two black and yellow wires under there, checking them for damage as we speak. Judging by damage to the wiring I doubt I'll be able to splice in my repairs, looking more and more like it may need a harness.

Beater EG

Update, car needs a harness, same white and green wire that was hot and melted under hood is melted under passenger side of the dash, fusing about 10-12 wires with it including the black and yellow wire that goes to fuse #24, so mystery solved after a few hours of playing with the power probe and tracking wires. Thank's for the suggestions that I received. Now if anyone knows anybody selling a complete harness that would be greatly appreciated.