I replaced a set of batteries after several years of good service and no issues. Replaced them with a set of advanced auto parts golds and after a month the batteries started showing signs again of issues mainly on cold starts at about 20°f and after sitting only over night(approx 10 hrs) after I cycle the glow plugs once it reads 10.x volts and is difficult to start. And batteries tested and only ends up pushing 1** some odd CCA. Replaced them with the same batteries. Now I'm having long start cycles after sitting a day. No electronic components really added and nothing that I can think of that draws while off. -alternator charges at about 14v give or take-
LB7: eating batteries
- Thread starter 02maxstang
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After shut down and sitting for about an hour it still reads a bit about 12 volts but it takes about 10 hours or so to read off around 11.7(ish)v. If I cycle my glow plugs it drops about a volt or so idk if its glow plug related. But I couldn't see it damaging a few sets of batteries and dropping the CCA so low in a short period of time. I'm in ct and I was going to run my truck to check my alternator amp outputs as suggested. But I'm in ct and enjoying this abundance of snow.. And the truck was dead and don't have a charger . So for now I'm stuck
My dad had a parasitic draw in his 04 Tahoe that we spent months trying to diagnose. Ended up being a resistor dealing with the HVAC system. I'll ask him specifically when I talk to him next.
if the alternator is not putting at least 14.3 volts at idle, it is bad and not maintaining your batteries.just thinking out loud.
I'm in Groton on the sub base. And I went out to my truck and it was about mid thigh and piles (from the wind) that are to my grille and a good ways up my doors. Idk what may count as an abundance to people who are from these parts. But I'm a transplant from the southern parts and its the most I remember seeing. But now I gotta wait till the morning and ding myself out and see if someone can jump me off so I can get to work on this.
Another thing you can try is putting an amp meter/clamp around your battery cables with engine off and see what the reading is, shouldn't have any reading but if you do, something is staying on, this is how I found my stuck glow plug relay, with engine off key off it was drawing 22amps, killed my batteries in about 2hrs.
Make sure you bought the correct batteries also. You need the highest CCA amps available. A friend of mine had a similar problem what had happened is they gave him the gasser equivalent battery for his make model and year.
So I had the batteries tested and they only show about 450 CCA when they're rated for 770. And the parts guy hooked up his fancy battery tester and it shows that the CCA fluctuate significantly between tests and(engine on/off) and says it may be a fluctuating charge alternator. But idk if I buy it because it still reads 14.7v-avg.(batteries both hooked up as well as tested independently)
There is no amp draw across both batteries when the engine is off. Im gonna go back out in about an hour and see if the v drop any then start it up and check the amp that alt puts out and see what that is
-does anyone know what the amp would be at the main battery for a stock alt?
And thanks for all the help. I do appreciate it. Hopefully I can get this worked out.
There is no amp draw across both batteries when the engine is off. Im gonna go back out in about an hour and see if the v drop any then start it up and check the amp that alt puts out and see what that is
-does anyone know what the amp would be at the main battery for a stock alt?
And thanks for all the help. I do appreciate it. Hopefully I can get this worked out.
Im in the process of trying to see if there is a parasite, im running the test light and pulling the fuse one at a time to see if I can pin point the system at least then try and track it down. If that doesn't provide any results ill take the alternator to the local ac delco shop and see if they can run a test and/or rebuild the alternator if it fails any tests.
as far as noticing alt fluctuation I don't have a reliable source to know for sure. I took it to 2 advanced auto parts and 2 autozones. Autozone says the alt passes their tester. One advanced tester wouldn't work(just read error) and the other advanced says the alternator is bad. And no offense to them but I wont fork out $200 on something if i'm/we/they not completely positive.
as far as noticing alt fluctuation I don't have a reliable source to know for sure. I took it to 2 advanced auto parts and 2 autozones. Autozone says the alt passes their tester. One advanced tester wouldn't work(just read error) and the other advanced says the alternator is bad. And no offense to them but I wont fork out $200 on something if i'm/we/they not completely positive.
How about the IC guage itself what does it read for volts? If its fluctuating that bad it must show up in the guage? 
if im not mistaken it reads just over 14 on a fairly regular basis and no DTC's/lights (other than my fuel gauge is jacked up, but that's another day) My brake controller(trailer brakes) says that im at like 14-14./6 ish.How about the IC guage itself what does it read for volts? If its fluctuating that bad it must show up in the guage?
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Makes no sense to me. If it was charging intermittently it should show up on the guage I would assume at some point. In addition the light would come on or perhaps throw a code.
I bet the batteries are junk.
I bet the batteries are junk.
I've been thinking that since this set is no more than a week old. Hard start/batteries struggled to turn it over after only a couple days. I want to return these batteries and get a set of AGM batteries or at least better ones from autozone, but since this is a total of 4 batteries that have turned up bad under my name. Advanced doesn't want to take back these batteries and they say that its something in my truck killing them. but ive only really had this issue with their specific ones, and only in the cold/coldish.
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