Have you seen my 4 volts?

[rwest]

I bought one of these to test my system, it was only $99, so thought what the heck. My system tested good, not surprising as it worked fine. Never tried it on a bad system though.

https://www.griotsgarage.com/product/battery+and+system+tester.do?from=ac

[FL911SC]

Joe Bob - Agree with you about replacing the battery. I am researching options now. I would like to stick with a gel battery, so I need to also find a way to mount it. One thing I liked about the Optima is I have a mount for it.

rwest - that is a good find. I may also pick up on since testing a car's battery is never and easy test.

[Trackrash]

It is easy enough to load test the battery yourself.

Charge battery. Disconnect charger.

Measure battery voltage.

Disconnect and ground the ignition cable.

Crank the motor for 10 seconds.

Measure voltage of battery.

Has the voltage dropped below 12 volts?

Watching the voltage drop during cranking can also give you an idea of the battery's health.

[al lkosmal]

Is your alternator light working? If it is not the charging system does not work.

regards,
al

[ant7]

Check and remove the earth strap from the starter [or elsewhere on the engine] to the body of the car, [right hand side rear when looking at the back of the car] this is a very troublesome connection, it may look ok, but it can cause serious resistance when it hasnt been cleaned in a while, once cleaned up, use copper slip on the connections when re-assembling, this will help maintane the continuity.
If you have already checked this then ignore my comments.
Good luck.
A...

[FL911SC]

After running some of the tests from the feedback, I had concluded that I had a bad battery. With that, I was ready to let this post fade into the archives.
However, I need to make one last remark to say, I found my 4 volts, and they were NOT were I was expecting them to be.

Today I picked up a Group 48 Bosch AGM battery to replace the Optima. The terminals are in a tricky position, but I figured I would get it to work since it is a good battery with a 4 year warranty. Anyway, before I put the battery in, I pulled out the trusty multimeter and took a reading... 9.8 volts. Hhhhhmmmmmmm Seems a bit strange to get the same reading that I got from the old batter from a new battery.
I found a different meter and put it on the battery, 12.3 volts! WHAT?! So I plugged the old meter into the wall, 86 volts (AC); then plugged the new one in, 120 volts.

Yep, the meter I was using was bad!! I checked the battery and fuses and when those were good, I tossed it. Now I am thinking about the wasted money (not really, it was probably close to due) on the new battery and all the other stuff I wrote off because of a bad meter. Sigh....

The good news is I found my 4 volts, they were there all along.

Thanks again to all.

[patz]

Good test equipment give good results. Glad you figured it out. That's why I have TWO Flukes.

[911pcars]

Originally Posted by patz

Good test equipment give good results. Glad you figured it out. That's why I have TWO Flukes.

One Fluke is quite sufficient unless an elephant steps on one. How many Porsches do you have? How many 13mm wrenches/sockets? How many hammers? I know. Probably more than one. A friend of mine has 25 electric/cordless drills.

A $4 HF multimeter is probably enough to confirm the open voltage of a car battery. Cheaper yet are the digital VMs that plug into the cig. lighter socket.

Sherwood

[Porboynz]

Originally Posted by FL911SC

After running some of the tests from the feedback, I had concluded that I had a bad battery. With that, I was ready to let this post fade into the archives.
However, I need to make one last remark to say, I found my 4 volts, and they were NOT were I was expecting them to be.

Today I picked up a Group 48 Bosch AGM battery to replace the Optima. The terminals are in a tricky position, but I figured I would get it to work since it is a good battery with a 4 year warranty. Anyway, before I put the battery in, I pulled out the trusty multimeter and took a reading... 9.8 volts. Hhhhhmmmmmmm Seems a bit strange to get the same reading that I got from the old batter from a new battery.
I found a different meter and put it on the battery, 12.3 volts! WHAT?! So I plugged the old meter into the wall, 86 volts (AC); then plugged the new one in, 120 volts.

Yep, the meter I was using was bad!! I checked the battery and fuses and when those were good, I tossed it. Now I am thinking about the wasted money (not really, it was probably close to due) on the new battery and all the other stuff I wrote off because of a bad meter. Sigh....

The good news is I found my 4 volts, they were there all along.

Thanks again to all.

Check and check again...........Once you have a known good battery check voltages again, but with a known good meter. Good luck fella.

Big call out for posting your dodgy meter findings.

[bpu699]

Originally Posted by Porboynz

Check and check again...........Once you have a known good battery check voltages again, but with a known good meter. Good luck fella.

Big call out for posting your dodgy meter findings.

Odd... I thought you said you were getting 13v at the alternator...

Why would the meter read correctly there?

Another thing to consider... optima batteries need a special charger... were you using the right one?

Either way, glad it worked out.