help ecu and alternator fuses keep blowing
94cordvtec
04-12-2009, 07:06 PM
ok so i have a 89 4 door civic with a b18b swap, last week i rear mounted the battery to the trunk and the car ran fine, today on easter got in the car and my battery light came on and i figured it would go off so i drove down the road and i heard a pop. well the battery fuse blew and blew the ecu and alternator fuse too, well i replaced the fuses and they keep blowing i unhooked the alternater power cable and plug and it still blew the fuse and t blows the fuse as soon as car goes to acc. and i wast getting spark either and my coil has power on the pos and neg. side in the distributor? idk whats going on the car has run fine all i can figure is its a ground problem, the trans used to be grounded to body and battery but isnt anymore so could this be the problem? do i need to ground engine or transmission somewhere else the motor is only grounded once from valve cover to body but everything just happened out of nowhere today, please help someone!
ctwright
04-12-2009, 07:12 PM
I love it when people answer their own questions. Yes it's a ground problem, and also possibly not the correct gauge wire going back to your battery. You may need thicker gauge since you are increasing the distance. Also too why did you rear mount the battery?
ctwright
04-12-2009, 07:17 PM
What do you have your ground hooked to now from the battery, you need to ground it down to the frame underneath the vehicle, and then in the engine compartment go from the frame up to your transmission bolt. That should help with the ground problem. And you might like I said go up another thickness with the wire that is going from the battery positive to the front of the vehicle.
94cordvtec
04-12-2009, 07:31 PM
ok its stinger amp wire its 5 gauge wire and its mounted on what i guess is a bolt coming thro the back of the trunk for the rear bumper support the car has run fine the last 5 days the battery has been in the trunk but as for the reason of rear mounting it is because i took a car with a 1.5L engine and put in a dual cam 1.8L the ls is huge in that engine bay and doesnt allow any room for an intake to run because the battery WAS in the way
ctwright
04-12-2009, 07:41 PM
ok its stinger amp wire its 5 gauge wire and its mounted on what i guess is a bolt coming thro the back of the trunk for the rear bumper support the car has run fine the last 5 days the battery has been in the trunk but as for the reason of rear mounting it is because i took a car with a 1.5L engine and put in a dual cam 1.8L the ls is huge in that engine bay and doesnt allow any room for an intake to run because the battery WAS in the way
I saw again where you said you swapped motors I figured that was probably it after I had posted. The way that works is it can run fine for awhile, you might have even had a tight connection but not a meant tight connection, meaning it getting its ground from a motor mount bolt or something. But you need to like I say make sure it is grounded solid to the frame near the rear of the vehicle, even clean off the area with a wire brush. And then from that same solid section of frame at the front of the vehicle do the same and go up to one of your transmission bolts. Then you will have a good solid permanent ground.
I saw again where you said you swapped motors I figured that was probably it after I had posted. The way that works is it can run fine for awhile, you might have even had a tight connection but not a meant tight connection, meaning it getting its ground from a motor mount bolt or something. But you need to like I say make sure it is grounded solid to the frame near the rear of the vehicle, even clean off the area with a wire brush. And then from that same solid section of frame at the front of the vehicle do the same and go up to one of your transmission bolts. Then you will have a good solid permanent ground.
94cordvtec
04-12-2009, 07:47 PM
so hopefully that should solve the blowing fuses problem? could it have done any permenant damage to alternator?
ctwright
04-12-2009, 07:50 PM
so hopefully that should solve the blowing fuses problem? could it have done any permenant damage to alternator?
I doubt it that's what the fuses are there for(to stop from burning up your wires and damaging components).
I doubt it that's what the fuses are there for(to stop from burning up your wires and damaging components).
94cordvtec
04-12-2009, 07:55 PM
well i apreciate yo its raining now, so i cant really get back outside to do anything right now so itll have to wait till tomorrow but thanks alot man
94cordvtec
04-14-2009, 10:00 AM
so i re routed and added grounds and still have the same problem i have burnt out the electronic load detector in the fuse box so im going to get a new one today and have come to conclusion the ecu is blown too so im ordering a coversion harness and using the ecu and dizzy,with alternator too cuz mine is trashed off the 93 integra i have for parts and spare motor and what not, but am going to retrace wires a 3rd time to double check no loose grounds or grounding power wire and try it again with new parts, hopefully it wont happen again :(
ctwright
04-14-2009, 05:04 PM
so i re routed and added grounds and still have the same problem i have burnt out the electronic load detector in the fuse box so im going to get a new one today and have come to conclusion the ecu is blown too so im ordering a coversion harness and using the ecu and dizzy,with alternator too cuz mine is trashed off the 93 integra i have for parts and spare motor and what not, but am going to retrace wires a 3rd time to double check no loose grounds or grounding power wire and try it again with new parts, hopefully it wont happen again :(
Sry that didn't help, it's hard for me to really tell exactly what is going on without looking at it, tried my best. I did notice though above that you said that you mentioned the size wire for ground, however I was asking about the size wire you used going up front for the battery positive, you should have went bigger than what was on it because of the extra distance.
Sry that didn't help, it's hard for me to really tell exactly what is going on without looking at it, tried my best. I did notice though above that you said that you mentioned the size wire for ground, however I was asking about the size wire you used going up front for the battery positive, you should have went bigger than what was on it because of the extra distance.
94cordvtec
04-18-2009, 08:23 PM
turns out to just be bad ecu, new obdo to obd1 harness came in today and i swapped for the obd1 ecu and dist, swapped the plugs over on the dizzy and she cranked right up, no blown fuses just need to swap over to 4 wire o2 and im done.
ctwright
04-19-2009, 08:50 AM
turns out to just be bad ecu, new obdo to obd1 harness came in today and i swapped for the obd1 ecu and dist, swapped the plugs over on the dizzy and she cranked right up, no blown fuses just need to swap over to 4 wire o2 and im done.
Well, I'm glad to hear you got it fixed.
Well, I'm glad to hear you got it fixed.
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