If you can help ill buy you a beer!

I have a 91 Civic Si I am using for a SPL car for car audio competitions.. 2 days ago I installed my HO alt which is externally regulated and everything worked fine. I took it to get a smog and so on and not one issue. The next morning I started it up and backed it out of the garage and left it running while i did a few things around the garage. Well I went inside and came back out about 10 mins later to leave to get the windows tinted and then it pretty much died.. I could start it and it would idle but as soon as i gavce it gas it would die.. Well i fixed that issue last night.. Now today it start fine, idles ok, and doesnt want to bog down or die when given gas.. But now as soon as my headlights are on or I press the brakes the car dies. It also make the RPMS gauge drop to zero and the temp gauge to jump to H?? LOL!! Once the car is started the rear and front corner lights are lightly illuminated which is not normal. Another funny thing is if the tail lights are not plug in the car wont start.. As soon as I connect the rear tail lights the car is then able to be started?? I am at a loss right now and have no idea what to do.. I have a huge car audio competition this Sunday and I am pretty much dead in the water..

Any advice is appreciated.. From the time my car was running perfect to its current state now there has been nothing done differently.

 

If the car was running fine before you installed the HO alt, have that tested. Sometimes you go through a few before you get a GOOD one.

Also you can raise the idle a little to keep it on.

 

My buddy had that exact same problem, check your battery terminals. My buddy's looked ok but they were worn and not making good contact. He replaced his battery and alternator before he figured it out.

 

It was running fine with my HO alt. I got the car running good and I just got HO alt dialed in.. Something is messed in my cars wiring.. Once the car is on all the corner illuminate very very low, and once I press the brakes or turn the headlights on the gauges go nuts and the car bogs down very bad and stalls. Its so frustrating lol!

Has anyone ever seen anything like this before?? All the local mechanics and Honda guys have no idea what the issue is. The conclusion is something in the wiring might be crossed and or grounding out somewhere

 

Ya its probably not the terminals. I have the grounds and power wire in 4ga and some in 1/0 with ring terminals with machine bolts to tight down into the Kinetik batts im using. My car is posessed!

 

If the car was running fine before you changed the alternator, and is now not running properly with the new alternator, then you can deduce where you should start troubleshooting. Many of the symptoms you've described here (stalling, backfeeding, etc.) are characteristic of an alternator that isn't charging and/or a drained battery.

You need to check all your grounds, check the fuse for the alternator circuit, and test the voltage that the alternator is producing first.

 

It actually worked fine with my new HO alt for a day lol...

Well I located the short to the fuse block under my hood.. It is the ECU fuse. With one lead from my DMM on the cars ground and the other lead on the batts neg terminal I am reading 12.5v Now I need to figure out where to trace the ECU wires to.. What a mess