Electrical 1990 GT battery drain...

John Dirks Jr

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The alternator is an upgraded 3G setup. I'll disconnect the alternator wiring and see if it has a measurable effect on the milliamp draw. Although I'm not sure if the 3G has the same potential to create these problems as the stock alternator.
 
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John Dirks Jr

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50 to 85 milliamps is one spec for draw on a car like yours 200 is more like a new lincoln with 5 modules and a radio

wait a sec, mine was drawing 20, not 200

That is after I removed all the interior bulbs so I could keep the hatch open while testing. It has a rear mount battery setup
 

manicmechanic007

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John,
Then your battery should hold for 10 to 14 days without a tender
And if it does not then the battery gets replaced even if it is a week old
 

John Dirks Jr

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John,
Then your battery should hold for 10 to 14 days without a tender
And if it does not then the battery gets replaced even if it is a week old
Okay thanks. So, if I have the battery connected, and I begin with full battery 12.6v, after 14 days, what voltage reading would still be considered acceptable?
 

manicmechanic007

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I would really just like to see you drive it more
I have a van I do not drive much and it goes through batteries
Same with my Corvette. They just need driven and none of that bad stuff happens
Once they get down below about 10.5 it will start turning on lights like the abs and air ride
 

7991LXnSHO

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So after a day of sitting it was down to 12.61V. About 8-10 hours later it was down to 12.55V. About a day after that it is at 12.5V. I will check one more time tomorrow morning, but it looks like it has more or less settled in around 12.5V if it only lost 0.05V in a day of sitting. So while it may not be perfect, I think the battery is at least decent, certainly good enough for starting a car in warm weather at least.

So I will keep looking around, mainly at the immobilizer and keyless entry/alarm system to see what I can figure out. Those areas seem to be the most likely to be causing this drain I think.
That the battery has not lost a lot of volts sitting there is not the same as a load test that helps see if it has any CCA or reserve power. At that low level of drain, I suspect you have two problems: 1. A weak battery 2. A small drain.

Please do the following:
Charge it up, hook it up, and get it to the FLAPS or Interstate battery dealer where the battery can be load tested and the charging system verified good.

The last battery I replaced in a car was charging up fine, but after sitting for 4 days would read good voltage, AND did not have enough amps to do more than make a horrible, repetitive clicking noise under the hood. It would charge up and run again. But it would do the same dying thing if parked. When “cranked” on a full charge with the tester, the load would pull the voltage down to 8.?v and it rebounded only partially. They warranted it and it’s great now.
 

manicmechanic007

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That the battery has not lost a lot of volts sitting there is not the same as a load test that helps see if it has any CCA or reserve power. At that low level of drain, I suspect you have two problems: 1. A weak battery 2. A small drain.

Please do the following:
Charge it up, hook it up, and get it to the FLAPS or Interstate battery dealer where the battery can be load tested and the charging system verified good.

The last battery I replaced in a car was charging up fine, but after sitting for 4 days would read good voltage, AND did not have enough amps to do more than make a horrible, repetitive clicking noise under the hood. It would charge up and run again. But it would do the same dying thing if parked. When “cranked” on a full charge with the tester, the load would pull the voltage down to 8.?v and it rebounded only partially. They warranted it and it’s great now.
Classic failure example +1 for Interstate
 

7991LXnSHO

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Yeah, Interstate batteries are just horrible. That's why I have one in everything I own, well cept the toyota, that cheap ass battery is still working.
I hope punctuation was missing and 007 was agreeing with me. :shrug:
Interstate batteries are good. They still need a warranty as lead acid batteries have a high failure rate, especially for the price.
 
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7991LXnSHO

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I found the privately owned FLAPS that sells Interstate batteries. I asked about a good battery for my Merc. For an Interstate battery, 850 CCA, three year flat warranty, $165. No more prorated extended warranties.
The local Napa store’s batteries are also flat rate warranties.
@Noobz347 and @General karthief etc. where are you getting the 7 year (84 month) warranty batteries now???
 

Noobz347

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I found the privately owned FLAPS that sells Interstate batteries. I asked about a good battery for my Merc. For an Interstate battery, 850 CCA, three year flat warranty, $165. No more prorated extended warranties.
The local Napa store’s batteries are also flat rate warranties.
@Noobz347 and @General karthief etc. where are you getting the 7 year (84 month) warranty batteries now???
Dealerships, I get mine from the GMC dealership down the street.
 
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Fri Guy

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I had a similar issue when my battery was moved to the rear. I had to add a good ground. Check your grounds.
 

John Dirks Jr

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My grounds are good and are over engineered actually.

I just got three of these Foval float chargers from Amazon. They are cheap and work great as a true float device. Read the first review written by the engineer. I have verified they work just like he describes. I already mounted one under the hood on the wife’s 2013 Escape since she hardly drives it. I’ll be mounting one in the rear mount battery box in the 92 LX as well. I’ll just unplug the wire from the hatch latch so the interior lights won’t come on when the hatch is open. While it’s in the garage sitting, just pop the hatch and plug it in. I’m also gonna install a cig 12v power outlet in the battery box. I have one of those compact lithium jump starters and I’ll keep it plugged in to the outlet in the battery box. It will always be there, fully charged if needed.

Here’s the Foval

Amazon product
View: https://www.amazon.com/dp/B074Z2NFWW/ref=cm_sw_r_sms_api_glt_i_dl_JWPB1MNZDWBBZMDH72ME
 

John Dirks Jr

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Here’s the Foval installed in the 2013 Escape. Believe it or not since new it’s had a defect in the sunroof motor which causes a parasitic draw of 200 milliamperes. I got tired of remote starting it every other day just to keep the battery up. So that, and the fact it doesn’t get driven enough is the reason for the float charger install.

On this install I have it wrapped in a ziplock baggy to provide some moisture protection. Don’t worry about it overheating because it’s only a 1 amp trickle max and hardly develops any heat.

The cord peeks out of the cowl for easy connection. The position of the charger even lets me monitor the status lights through the body seam when the hood is closed.

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