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I just changed alternator, car still won’t start

Please help!!! I just changed the alternator and car still won’t start…tried boosting it but no turnover…

Check your cables and ground connections. Old fart here used to hit the pos stud on the starter motor with a jumper cable from the pos of the battery, but not sure if that works on these new fangled cars. Make sure the battery is not shot.

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Thanks…starter is under the engine, would have to jack a side to get to it…the battery is a red top, i guess expensive kind and previous owner said its fairly new…even if battery is dead a boost would still work? Thanks

If the battery is too fried a jump can fail. Check the free stuff first, connections, fusible link if applicable etc.

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Why did you change the alternator? What symptoms did you have that led you to changing the alternator?

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You need to properly charge the battery before condemning the starter… Not all boost packs are created equal (not by a long shot) and a jump doesn’t work with a completely discharged battery, especially a battery that has likely been abused by a failing alternator / discharged state situation for who knows how long. The battery you are putting so much faith in because it was expensive is not how it works…if that expensive batt is internally damaged or dead…a jump or boost wont compensate for the hole (or power black hole) that battery now represents. Its better to not have a damaged battery in the loop if you are trying to jump a vehicle.

See if the battery can be properly charged…and holds a charge…then reinstall. if the batt doesn’t come back to life, you found the problem… do not replace anything else until this is done. You need a good charged batt before moving on…

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I reinstalled my barn door and carefully closed it last night but this morning my cows still aren’t there.

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Shift the transmission into neutral and then try starting the engine.

Tester

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Was driving then car died, got a boost then two minites later same thing, then again…stereo lights were off, wipers moving slowly, nothing else working…then i popped the hood and there was abit of corrosion under pos terminal, so i cleaned it, ordered new alternator and replaced it…gonna go charge battery today…found someone with battery charger and multi meter…thanks guys

you can start a car with no alternator attached. But you cannot start a car with a dead battery, and if it is dead enough, a jump won’t do anything either. get the battery charged and checked (including a load test of some sort after charging.)

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Maybe you have trouble with the starter motor.
Anyway, check wires between the battery, alternator and starter. Also, check ground wire between engine and body.

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Battery reads 4.6 volts

4.6V? Dunfer!

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What you are describing here is textbook alternator failure… The reason you could run for two minutes was from the jump actually charging the battery…then you used up that partial charge and the engine died again…because the alternator is not providing power.

Please perform the steps I outlined prior… Charge the batt… reinstall…start vehicle and test running voltage…and also test voltage with engine off…

Report back. If your alternator is healthy it sounds like you will be ok…just judging from how your battery accepted the charge from the last jump… that is promising news.

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I got battery charged (battery from van) and theres power now but car isn’t starting…has power tho

Not sure if anti-theft disables starter on cars or just ignition? Maybe it varies from brands?

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All lights and electrical is turning on except engine , sounds like it want’s to start but not quite…could it be fuel pump? Spark plug? Fuse link? Also the anti theft light flashes on and off…could that prevent me from starting car? Thanks

Car is now running, Anti theft system must have been activated after switching batteries, it’s now disabled and vehicle is running again!
Thanks for all the help guys, its much appreciated

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I once had a VW bus conversion to power an American 6 cylinder engine. The owner could not get the vehicle to start, replaced the, starter, battery, all the relays, and lastly the Alternator that is when I came in, it turned out to be the positive cable which is longer then most cables was defective stopping most of the battery power from getting to the starter.