Battery woes

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nico boom
Deus ex MS
Deus ex MS
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Re: Battery woes

Post by nico boom »

You mean with the battery connected using a amp meter between the battery-pole and car I guess?
We perform this simple test with two persons; one looking at the meter [which has to be able to read low- and high amps], the other one pulling out the fuses one-by-one, the first looking for a amp-drop.
I think Tom did this already, as his amp-loss with the car just sitting there simply is too high.
When you haven't did this already Tom, you could ask Wendy to help you out watching the DMM [after all you're the master of the house now..], to find what's eating up that current.
Worst case scenario; a partially short in your cable-harness....we've had those many times in the old cars at work.
Also in motorcycles this type of amp-draw-problems is more common and sometimes very hard to find.
Finding a partially short with freeze spray will save you a lot of time as it obviously will produce a little bit of heat.
Performing the simple test described above with the DMM should point you in the right direction. [I have been forced to completely take apart a cable-harness once to find a wire that was only making contact with a few strands on a bike that spontaniously stalled many times when driving... :evil: ].
Good luck
Nico
Virtue
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Re: Battery woes

Post by Virtue »

I really would not point at the battery as the problem. Let's see, the battery was tested and it put out 750 amps. Your alternator reads 14.4 volts. So, IMHO, I would check an issue with starter... I bet you have a poor ground wire from the engine block, back to the battery and chassis, maybe rusty connections. If it is not the ground wire, then you might have a bad positive wire going from the alternator, battery, then to the starter. Loose wire to the starter? Maybe the starter is loose on the engine block. If these are checked and all good, have the vehicle run, turn the stereo on and then check the DMM. It is possible the alternator is putting out 14.4 volts but when there is a small load, it might not be charging the battery. Giving an answer as a bad wire or connection from the alternator to the battery... Maybe a flaky alternator...
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stipud
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Re: Battery woes

Post by stipud »

So far, so good with the new battery. No starting issues, and there is minimal battery voltage sag overnight. Car starts up as easily on the first start of the day as it does with a fully charged battery. Basically it seems to be back to normal.

I've been trying to track down the source of the current draw, because I agree 100mA is higher than normal. I ran through the fuse test yesterday, and the results were... inconclusive. The only thing I could get to seriously affect the current draw, at all, was pulling the ECU fuse. But that brought it down to well under 10mA... which is way lower than spec. So it's either the ECU, or something that needs communication with the ECU to run. Alarm perhaps? Pulling the alarm fuse on its own only dropped the load by 5mA, which seems reasonable. I have an old stock ECU I will be swapping back in to see if that makes a difference.
Virtue wrote:I really would not point at the battery as the problem. Let's see, the battery was tested and it put out 750 amps. Your alternator reads 14.4 volts. So, IMHO, I would check an issue with starter... I bet you have a poor ground wire from the engine block, back to the battery and chassis, maybe rusty connections. If it is not the ground wire, then you might have a bad positive wire going from the alternator, battery, then to the starter. Loose wire to the starter? Maybe the starter is loose on the engine block. If these are checked and all good, have the vehicle run, turn the stereo on and then check the DMM. It is possible the alternator is putting out 14.4 volts but when there is a small load, it might not be charging the battery. Giving an answer as a bad wire or connection from the alternator to the battery... Maybe a flaky alternator...
Alternator has a 0 gauge ground directly to it, as well as the body, in addition to the two stock 4 gauge grounds. Starter connection is tight. Alternator is a freshly built 200 amp externally regulated Wrangler NW. When the battery would die, it would take out all electronics in the car... not just the starter.
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Thunderdome
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Re: Battery woes

Post by Thunderdome »

hey wow late to the party again..

I was having the same probs with my optimas in my rx-7 cause it sits a lot the battery just kept dying but my daily driver was allways fine, battery would just die sometimes 1 day sometimes a couple days. I ended going to the new Kinetik AGM battery for the rx-7 so while I,m talking with my buddy and picking up the new batt he tells me to only charge it with a agm charger and that the optimas should also be using this same charger as they desulfate the batteries while charging and that he had brought back more then a few using this type of charger on them, they sell the chargers at ctc
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Remember: The chart serves only as a starting point. Ultimately you must use your ears as a guide.
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