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Stock battery leaking acid?

SmoothCat565

Go Kart Newbie
Location
Massachusetts
Car(s)
2017 VW MKVII GTI
Looks like battery is leaking acid underneath. Battery is stock so 6 years old now. Terminals are clean. Probably cracked on the bottom.

Disconnect, clean, and check for any new acid leaks or just get a new battery?

Anyone had issues with their tunes when switching batteries?
 

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Nyulak

Ready to race!
Location
SheffVill, OH
My local shop noticed my stock battery leaked after about four years of life. I had them replace it without any impact. They specialize in VAG products, so they might have done something else, but I doubt a battery swap would ever impact a flash tune.
 

DSC808

Autocross Champion
Location
HI State
Car(s)
2016 GTI SE MT
I had that. Tried baking soda and washing it off. Now its got that sh!t all over the transmission case. Only I ever see it... but I know its there....... ... .... . .
So yea maybe when you replace the battery you take out the tray (couple 10mm nuts/screws) and then rinse it off.
 

YamR1rider

Drag Racing Champion
Location
Tampa, FL
Car(s)
2017 GTI Sport DSG
Just get a new battery before it gives up the ghost. You've for sure had your money's worth out of that stocker - many (including mine) fail at half that life or less
 

SmoothCat565

Go Kart Newbie
Location
Massachusetts
Car(s)
2017 VW MKVII GTI
Just get a new battery before it gives up the ghost. You've for sure had your money's worth out of that stocker - many (including mine) fail at half that life or less
Before it gives up the ghost lmao

I know I’m trying to figure out which one to get
 

tmw2442

Autocross Newbie
Location
Approved NPC storage contanier
Car(s)
Mk7 R
Before it gives up the ghost lmao

I know I’m trying to figure out which one to get
Group 47 agm battery, then code it properly in the BCM via vagcom or odb11....multi threads on this forum and youtude videos about batteries...and coding them...

The thing about batteries is....most of them are made in about 3-4 factories across the globe and 15 distributors put their brand sticker on them....when you go to autozone and buy a standard...gold or platinum battery....the battery is identical and you are paying for a 2, 3, or 4 year+ warranty. Unless you are buying some bougie lithium stuff....which unless you are actually really racing...is irrelevant.

Regardless of the battery still starting the car....after about 4 to 5 years....they are on borrowed time, and you are actually putting the car's electrical system on increased strain, wear, and tear....pushing current through a older battery as the internal resistance (getting angry pixies in and out....) goes up as the battery ages....anytime you see any amount of corrosion ....that battery is on its way out and needs replaced...
 
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SmoothCat565

Go Kart Newbie
Location
Massachusetts
Car(s)
2017 VW MKVII GTI
Group 47 agm battery, then code it properly in the BCM via vagcom or odb11....multi threads on this forum and youtude videos about batteries...and coding them...

The thing about batteries is....most of them are made in about 3-4 factories across the globe and 15 distributors put their brand sticker on them....when you go to autozone and buy a standard...gold or platinum battery....the battery is identical and you are paying for a 2, 3, or 4 year+ warranty. Unless you are buying some bougie lithium stuff....which unless you are actually really racing...is irrelevant.

Regardless of the battery still starting the car....after about 4 to 5 years....they are on borrowed time, and you are actually putting the car's electrical system on increased strain, wear, and tear....pushing current through a older battery as the internal resistance (getting angry pixies in and out....) goes up as the battery ages....anytime you see any amount of corrosion ....that battery is on its way out and needs replaced...
appreciate the headsup. I was told by volkswagen that there is no coding required when installing a new battery lol. i'm all for purchasing an obd11 if I need to do it correctly, but volkswagen is either wrong about this and recommending no coding incorrectly or the coding is pointless. as far is which is correct, I have no idea at this point. all the threads are either "it matters" or "it doesn't matter".
 

tmw2442

Autocross Newbie
Location
Approved NPC storage contanier
Car(s)
Mk7 R
appreciate the headsup. I was told by volkswagen that there is no coding required when installing a new battery lol. i'm all for purchasing an obd11 if I need to do it correctly, but volkswagen is either wrong about this and recommending no coding incorrectly or the coding is pointless. as far is which is correct, I have no idea at this point. all the threads are either "it matters" or "it doesn't matter".
sure...if you install an identical oem battery...from Volkswagen...dealer

if you want to get the most life out of the battery you purchased....code the BCM of the car appropriately, if especially, you are changing group size, as group 47,48,49 sized batteries fit the tray. Most US cars came with a group 48. Is a giant meteor going to hit the earth if you don't no....telling the car the estimated reserve capacity, and amp hrs allows it to accurately manage the life of the battery better. the difference in size is 47 are around 32lbs, 48s are 41 lbs and 49s are 50 lbs...amp/hrs goes from around 60-80-100...its why the car knowing is better, and the float voltages change with the design (agm, vs gel, vs flooded)....supplying too much float voltage can shorten the life. If you are going to long term own a VW, an odb11 or vagcom is a great too, worth its price, with what you can do with it....investing in one is a good idea...
 
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YamR1rider

Drag Racing Champion
Location
Tampa, FL
Car(s)
2017 GTI Sport DSG
For this last replacement I just got the cheapest possible standard spec replacement battery I could find (which happened to be a group 47/H5 Valucraft from Autozone at around $109 with a discount). As poster above says, a lot of upselling is just buying warranties (and the batteries always seem to crap out just after the warranties fail....). The battery I got was very close in stats to the factory ones so didn't really need coded (and I'm not convinced NA cars without stop/start need coding anyway, regardless of size of replacement)...but as I have OBDEleven I went in and registered/'coded' the battery change anyway - I just use the installation date to keep track of it.
 

SmoothCat565

Go Kart Newbie
Location
Massachusetts
Car(s)
2017 VW MKVII GTI
anyone know how to find the battery PR code on this car 2017 gti

odysseys website has two different batteries listed depending on that code and it’s no where to be found on my car. Checked the owners manual.

alternate way to determine the battery PR code?

got the group 48 H6 delivered to me. But depending on the pr code, I might’ve needed the group 47 H5. I have a 50% chance I bought the right battery right now.

was ready to install and then stopped. Looks like I’m calling VW and Odyssey next.

Here is what the odyssey website shows:
J0H
ODP-AGM47 H5 L2
(47-650 (LN2-H5))

J0N
ODP-AGM47 H5 L2
(47-650 (LN2-H5))

J0S
ODP-AGM47 H5 L2
(47-650 (LN2-H5))

J0T
ODP-AGM48 H6 L3
(48-720 (LN3- H6))

J1D
ODP-AGM48 H6 L3
(48-720 (LN3- H6))

J1L ODP-AGM47 H5 L2
(47-650 (LN2-H5))

J1P
None

J2D
ODP-AGM48 H6 L3
(48-720 (LN3- H6))

J2S
None
 
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tmw2442

Autocross Newbie
Location
Approved NPC storage contanier
Car(s)
Mk7 R
h6...h5 both fit...
 

SmoothCat565

Go Kart Newbie
Location
Massachusetts
Car(s)
2017 VW MKVII GTI
h6...h5 both fit...
How can they both fit if they have entirely different data sheet values for every parameter (CCA, HCA, MCA, capacity, internal resistance, short circuit current, reserve capacity, etc)? It’s not just a dimensions thing. odyssey is specifying a h5 or h6 depending on the PR code.

Heads-up, apparently AGM should be entered to OBD11 as “fleece” not “binary AGM”, counterintuitively. Humble mechanic says do binary AGM, and I trust his channel, but lots of people are like nah it’s not that it’s fleece….humble said he doesn’t think it should matter
 
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avenali312

Autocross Champion
Location
Mableton, GA
Car(s)
2015 GTI
Heads-up, apparently AGM should be entered to OBD11 as “fleece” not “binary AGM”, counterintuitively. Humble mechanic says do binary AGM, and I trust his channel, but lots of people are like nah it’s not that it’s fleece….humble said he doesn’t think it should matter
AGM = Fleece, at least based on quite a bit of back on forth on here. I know that @StealthGTI took the time to update his battery coding video, or at least add a comment in there explaining it.

Edit: Found it. He added a comment.


1687185914324.png
 
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tmw2442

Autocross Newbie
Location
Approved NPC storage contanier
Car(s)
Mk7 R
How can they both fit if they have entirely different data sheet values for every parameter (CCA, HCA, MCA, capacity, internal resistance, short circuit current, reserve capacity, etc)? It’s not just a dimensions thing. odyssey is specifying a h5 or h6 depending on the PR code.

Heads-up, apparently AGM should be entered to OBD11 as “fleece” not “binary AGM”, counterintuitively. Humble mechanic says do binary AGM, and I trust his channel, but lots of people are like nah it’s not that it’s fleece….humble said he doesn’t think it should matter
That's why you code(the reserve capacity,etc...)...and fleece is the answer; the lower the internal resistance the better the battery. Odyssey wants the PR code off the battery to pick the exact spec battery replacement, doesn't mean another spec doesn't work. The car doesn't really care...once it's coded, h5, h6, H7s all fit in the tray...as my previous post, even H4 as well...because lightweight racecar, all fit and will work.

https://batterygroupexpert.com/battery-group-size-chart-and-cross-reference-table/

H4...is LN1...is group 140
H5...is LN2...is....group 47
H6...is...etc...I am amusing you are picking this up...use the link above...

ALL YOU HAVE TO BE SURE OF IS THE BATTERY POSTS (+ and -) are in the correct positions... usually by the group number or the group number having an R moniker at the end...(polarity swapped/positive terminal position....)

Some companies will even sell the H4...which is LN1...which is group 140....at different prices...but the same battery...so...if you are in the know...you save $20 - $50 bucks... The prices are set by demand....if everyone comes in and asks for a H5....prices go up....if no one buys LN2s...the prices go down....etc...they are functionally the same...sometimes the businesses don't care to figure it out and put they all in the same purchase buckets...

I don't know how much easier I can explain this...I have had H4s, H5s, group 140s, H6s...in 4 VWs Mk5 and UP....since 2007...and they all work...the cars have lego parts.

I normally put H4(s) if I am concerned about weight...I added 7 more lbs of intercooler on the front of my car...so I put an H4 in a car that came with an H5...about 8-10 lbs lighter....NET zero...

IF you are not driving your car......
With modern VWs...they pull 40 to 50 mAmps from the battery in sleep (locked with they key more than 25-30 feet away(KESSY is always looking...) (or about to a little over an AMP/HR a day)....so the greater the reserve (bigger the battery)....the longer you can let your car sit...before the lead acid chemistry battery drains 50-60 percent charge, which you never want a battery to get below....So in my testing on a golf r....a deka etx30(20lb harley motorcycle battery), lasts about 10-12 days before you want to plug in a tender...an H4 about 3 weeks, H5 about a month tops....H6/H7 5-6 weeks. Will a 50 percent charged healthy battery start the car yes...will it put additional wear on the the battery, yes.

Generally....
etx30 (harely/side by side 20lbs battery)...lasts about 2.5ish tops, needs replaced (minimum I would consider for a daily...) 3 years if you want to keep it on life support .... (battery tender plugged in once the car/battery cooled off...and tend it overnight).
H4/h5 about 3.5 to 4 years (32 to 40 lbs)
h6/h7....4 to 5.... (46-53 lbs)
regardless after 5...you should just swap in a fresh battery...imo

I have found most new batteries have an internal resistance in a range of 2 to 5 on my tester(depending on manufactuer date to purchase date)....and after about 10 plus... depending on full charge voltage and drop overnight(below about 12.6 overnight, from a full topped of charge from a cool battery).....the battery is what I would call starting to be unreliable/end of life..and should be swapped...imo

because of heat buildup in the engine bay, they generally live when charged by the car around 80 to 90 percent charged most of the time...12.65 to 12.75 ish resting....Remember also your car runs a coolant afterrun pump for 5 or so mins after you shut off the car, so if you check voltage during that time, since the battery is under a load, you'll see 12.5-12.6 volts...until the car goes to sleep....not locking your car in the garage generally extends modules sleep timer...locking it, send it to sleep mode faster, but these cars...never really turn off....like a corolla or civic of the late 90s/early 2000s.

SO...if you have a perfectly healthy 100 percent new battery...with an AMP/HR capacity of 60, and as a good practice....you never want a battery to go below 50 percent charge as it ages the cells faster.....shortens the batteries life....you need to plug your car into a tender at day 30...or before....if not driving...

Habitually abusing the battery half a dozen times at below 40-50 percent charge (11.9 to 12v) and you don't tend/charge it back up to around 70 percent (12.3-12.4 before you ask it to start the car), is enough abuse to shorten it's functional life to 2 ish years.

Live in the frozen tundra of the North or the deserts of Las Vegas...3 years out of battery is good. Moderate climates 4-5....

IF...your car sits at an airport, or dock yard, or in your garage while you go on 2 week trips for work buy the bigger battery....if you daily drive daily....the smaller battery works just fine...if your car sits outside and it's freezing...buy the larger battery. IF you have start/stop...and don't have is disabled in some way....at least buy an H5 minimum. Would recommend the H6 for normies...who don't understand, how they are abusing their vehicles...

IF...your keyed on screwing around with ODB11 or Vagcom without a battery charger hooked up supplying at least 6-8 Amps...you have 20 mins....tops to screw around (25-30 mins on a trickle charger), with the charger hooked up (6+ amps), keyed on you have 45 to an hr, but you are at a couple amp deficit, if you have a professional grade charger that gives more than 10+ amps...you can probably keep the car on indefinitely. 🤷‍♂️

All the analysis is here for you....and you didn't have to search it on your own.... :ROFLMAO:
 
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