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New Rebuild Not Starting

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Old Aug 4, 2024 | 09:34 PM
  #1  
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Default New Rebuild Not Starting

Just rebuilt my engine plugged everything in and was ready to start the car. First turn of the key everything came on as normal. Dash lights turned on all my gauges did the start sequence and all lights came on and went away as a normal start. I had fuel pump disconnected to prime the system first. I cranked it and the engine didn’t turn over.

I thought the battery didn’t have enough juice so I charger it with a mini jump pack. Then bought another actually big jump pack and charged it and still not start yet. Tho now and every attempt after the first when I put the key to accessory mode or almost to start. I don’t get any start sequence anymore. No warning lights, mileage, or start sequence of the gauges.

The headlights work. Dash gets lights illuminated behind it when those are on. Battery tested at 12.18 it was new before the rebuild but has been sitting for a few months.

Not sure if the first time when it “worked” almost as normal I blew a fuse or something? What main fuse would make my start sequence go away? Fuel pump doesn’t get power when plugged in. I believe all my grounds in the harness are correct. Just not sure why it “worked” once but then won’t light up again.

Or if battery is just dead and needs a jump? I’m going to jump start it with a car tomorrow or buy a new battery and return it if need be. Any suggestions or things to look for help.
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Old Aug 5, 2024 | 01:19 AM
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12.18 volts open circuit is a discharged battery.
If your fuel rails were dry, it can take several (2 second) prime cycles from the PCM to fill the rails with fuel.
Do you have, or can you borrow a Battery Charger ?
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Old Aug 5, 2024 | 08:06 AM
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Agree with the battery dead suggestion above, but the varying symptoms could also suggest a major ground issue...

Best, Nick
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Old Aug 5, 2024 | 11:13 AM
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Just got a new battery, put her in and nothing. No dash lights no start sequence. Any ideas a what fuse might’ve blown? Or what I could’ve wired backwards for this to happen?
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Old Aug 5, 2024 | 11:23 AM
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Have you checked starter and other relays?
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Old Aug 5, 2024 | 11:44 AM
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That’s exactly what I just checked and it was that. I accidentally miswired my starter. The black lead that is supposed to go to the block I accidentally attached to the starter. Now, after putting it in, it’s correct position still no dash lights. Should I replace the starter fuse?
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Old Aug 5, 2024 | 12:01 PM
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Relays and fuses are cheap and if they continually blow, that’s the circuit with the issue. I have had issues with relays like you’re describing. Sounds like you’re on the right path. I always check them all just to eliminate them from possibility.
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Old Aug 5, 2024 | 12:39 PM
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After putting the ground wire that goes to the block on the starter by accident. I replaced the large starter relay. No effect. Then swapped the ignition relay with the good fuse as well. No start. Not sure what to look for next.
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Old Aug 5, 2024 | 12:42 PM
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Think I found it 50 amp fuse for ignition broken. Going to the store to buy another right now let’s see if it works.
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Old Aug 5, 2024 | 01:16 PM
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Yikes blown 50 Amp Fuse your issue is in that circuit most likely a short to ground. Which you’ve described with grounding the starter. Double check all wiring in that circuit
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Old Aug 5, 2024 | 01:27 PM
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Replaced 50 amp, ignition fuse, and that fixed the problem. Dash lights came on everything finally worked. Went to crank it still with fuel pump relay unplugged and as soon as I cranked, it had a big thud and now dash lights don’t work again. I turned the motor over by hand with a wrench still turns over just fine. Motor isn’t locked up. I checked the 50 amp fuse again and it’s not broken but still now having the same issue.
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Old Aug 5, 2024 | 01:34 PM
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Has to be some kind of grounding issue somewhere. The main battery harness goes to the starter with a positive wire. Then has that ground that goes to the block above it.
Then has a wire that leads all the way to the alternator. And the red wire that comes up to the fuse boxes.
There is a thin copper wire that I believe is just ground strap. I have it grounded to the block on the driver side. But then the other side of the copper strap, I grounded to the chassis. I put it on the ABS bracket. I don’t believe that is the correct spot for it, but should theoretically work I believe. I don’t understand how this strap just goes from the chassis to the block. What does that do?

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Old Aug 5, 2024 | 01:49 PM
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Put the fuel pump relay back in. Check every other relay and fuse associated with the starting circuit. If they’re good move to all wiring associated with those circuits.
Other things to check
Is the neutral safety switch faulty, crank or cam sensors?
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Old Aug 5, 2024 | 02:02 PM
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It pretty difficult to have too many ground straps but you only need them to go where the factory wanted them to go. I would not ground to an ABS Bracket permanently.
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Old Aug 5, 2024 | 02:09 PM
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Also make sure your relays are properly oriented. With the “numbered” prongs going into the correct slot of the fuse panel, if that makes sense.
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