Question about 1987 Nissan 300ZX

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Low voltage I'm having a problem with a new alternator and battery not giving me a higher voltage reading.Want I'm reading is about 9 on my gauge

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Clean all connections and make sure they are sound on both the battery and alternator. Electricity does not like to flow properly through dirty and poor connections.

If your alternator is not pushing charge at over +13V(sometimes over 14V, all depends) when the engine is running, then it is faulty. Take it back to where you bought it from and exchange for another.

If the alternator is fine whilst running and the battery shows 9V when the engine is stopped, then your battery is not holding the charge and is faulty. Take it back, same as if the alternator were faulty.

By rights, all things being equal, once started, your engine should run without the battery being connected at all, if your alternator is operating correctly. Your battery is only a storage device to initiate engine ignition. They are rated by CCA, which is simply crank power to turn the engine over and start.

Posted on Mar 19, 2014


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