957 Cayenne S 2007 battery issues

[Andystocker]

I hope someone can help me - I've had my S for 5 years now and it has been solid. The only think that has been a problem is the battery - I am on my 3rd one now and am about to change it again. When I got the car it would sometimes not turn over on the first crank - not a problem always worked the second time. It bothered me so I changed the battery for a Yuasa HSB020 - which fitted perfectly and worked a treat. About a year later the battery started to show the same issues as the last one and gave up - which is a pain as changing the battery when the battery is dead is nearly impossible - You need power to move the passenger seat about! Anyway I did it and it was sorted - Halfords changed the battery without hesitation. A 2 years later the same thing happened and I swapped the battery again - for free. I am getting very good at changing the battery now but have been told that an AGM battery would be a better option and should not suffer the same fate as a normal one. The things is that the AGM battery is not specified for the 957, as far as I can see and I believe that the charging of them is different. Has anyone had the same problem and got a resolution? AGM batteries are not much more expensive and I would prefer not to swap my battery every other year!
Cheers
Andy

 

[Motorhead]

Andy,

I presume that your Cayenne doesn’t have stop-start for which an AGM battery is a standard fitment? I believe that they have a lower internal resistance and a faster charging rate than a lead-acid battery and in principle I don’t think that there would be a problem … however, that’s not guaranteed! I suppose that a lot depends upon the charging circuit and whether or not it’s monitored, which I believe is what happens in later cars when an AGM battery is fitted. My 2009 987.2 Cayman has a lead-acid battery which I don’t think has battery voltage monitoring whereas the later 2012 981-series cars which feature stop-start and an AGM battery do.

Rather than keep changing the battery, I would have thought that it’s more important to investigate why the batteries keep failing since three batteries in 5-years seems very excessive to me, especially if the car is used regularly. Have you checked the battery voltage ignition-off and when the engine’s running? Keeping the battery on a conditioner when the car’s not in use should also prolong battery life.

Jeff

 

[Andystocker]

Hi Jeff
Thank you for you reply - My mechanic has looked at the charging and voltages and everything checks out. Unfortunately I live in West London and park on the street - so I cant add a mains powered conditioner but maybe a solar one might help but I do use the car frequently.
Maybe the Yuasa is not good enough for the job? This one has not failed yet and maybe I'm worrying over nothing! The odd thing is that the battery will struggle to start when the car is warm. If I go for a long or short drive, switch the engine off and then restart it more often than not it hesitates - crank again and its fine - which goes against physics in my opinion.
It would be interesting to see if anyone has tried an AGM in a 957.
I'll probably change it soon - seems pointless to get a replacement from Halfords as it will happen again - maybe I should go for a Bosch?

Andy

 

[swiftus]

Hello,
I replaced the battery on my 955 every 2 years or so, and that was using a heavy duty high ampage unit; that wasn't an eye brow raiser for the place that looked after my car. I must of had 4 batteries over 9 years.
Later it did develop an occasional sporadic battery drain. This was traced to a rear door pack (that contains the locking, window control, alarms etc). It was tricky to find as it only drained sometimes. The clue was that sometimes you could hear the door lock operating when it shouldn't have been.
Hope that helps.

 

[Andystocker]

Hi
Thanks for this - this does tally with other reports I've found on google. I have just emailed Porsche West London to ask them what the correct battery is - but will probably get another replacement from Halfords.
I like you Had list and your Have is pretty cool too! The 996 Turbo has always been a looker but the more standard ones are growing on me now but still looking for 997!
Have a great day.

 

[Motorhead]

Tracing rogue battery drains can be a nightmare Andy, but since you have problems starting when the engine is warm it doesn’t sound as though that’s your problem … maybe that’s more a fuelling or ignition issue? However, it may be just as well to check obvious sources like bonnet, boot and glove compartment lights remaining on when the ignition’s off.

The Yuasa is a decent-quality battery so I wouldn’t have thought it to be an issue but as you say, maybe you should go either for Bosch or Varta next time?

Jeff

 

[Andystocker]

Hi Jeff

It doesn't add up - in 2019 the battery died so a doubt it's a mechanical issue but you never know. Porsche west London quoted £603 for a battery and fitting - which is not cheap but might be worth it if they fix the problem. They did say they code the car to the battery - but I cant see that as a solution. When I've changed the battery the car had a suspension fault that resolves itself when you switch the car off and on - Common and to be expected. Interesting my 987 had an iffy coil that would throw up a fault and give a check engine but would go away when the car restarted - which I've never had before - ive always had to hook the car up to a computer to clear a check engine light on the dash.
My daughter drives it more than.me and said it definitely only happens when warm and always starts on the second try. I don't want her to gey stranded but she seems not to be worried so maybe ill see how it goes as it gets colder.

 

[stevehaley]

I have a lithium battery starter which is wonderful. Very easy to use and keeps it charge.
mine isnt made anymore but it is something like 5his
https://www.amazon.co.uk/Lithium-Starter-Upgrade-30000mAh-Gasoline/dp/B09C34P58R/ref=sr_1_13?crid=VS49DQ3INBE3&dchild=1&keywords=battery+starter+pack+for+car&qid=1632244084&qsid=259-7239741-7661750&sprefix=Battery+start%2Caps%2C156&sr=8-13&sres=B015TKUPIC%2CB0924V8SPC%2CB00FB7LTO8%2CB09BZCHY7K%2CB015TKSSB8%2CB015TKPT1A%2CB00DGSCEUC%2CB08WZFPXFM%2CB09C34P58R%2CB08WYKD6TY%2CB0985TM2T7%2CB099J65581%2CB09C247B3L%2CB016UG6PWE%2CB07MVY7K43%2CB09C61VHZG%2CB08WZKRHZZ%2CB09D7HMMGY%2CB095LBC8FD%2CB095T1K7CR&srpt=JUMP_STARTER

 

[Octane]

Hi Andy,

you didn't mention anything about charging or testing the battery. What has been happening when you say it fails? For instance if you have the Porsche "charge-o-mat" (= CTEK MKS) this charger tests the battery both at the start and end of charging. Failure to hold charge is indicated by the error light.
Especially in winter it is beneficial for the battery life to charge it fully every few weeks even if the car is starting OK. This is because in normal use, it isn't charged for long enough reach high charge and it loses charge more in low temp. Also, for models with auto stop/start that is going to deplete the charge more.
Tech details here: https://batteryuniversity.com/article/bu-804-how-to-prolong-lead-acid-batteries
[blockquote]" ... give the battery a fully saturated charge once every few weeks. If at all possible, operate at moderate temperature and avoid deep discharges; charge as often as you can... "
[/blockquote]I charge mine on the street using a cable protector across the pavement. People might think it a hybrid and not not look so disapprovingly at the V8
[blockquote]"Porsche west London quoted £603 for a battery and fitting"
[/blockquote]Seems like a bit of a fiddle to access but that is incredibly expensive. I guess it should be £125 for the battery plus 1hr labour, so £200 at an indy.

 

[Andystocker]

Thanks for the link and info - As I live on a main road I park at least 50 yards from my house - running a cable is not an option!
From all the helpful advice here I am going to get my garage to give the battery and charging a good going over and see what that throws up.
I might need to wait until I can get some petrol first!

 

[graham.webb]

Just had a new battery for the 944 S2 from Halfords...a Yuasa, made in Ebbw Vale.
The 944 re learns its (simpler!) settings, but some years ago Halfords fitted a new battery to our SAAB and they plugged a slave battery into the cigar lighter to keep everything powered up so settings weren't lost. Clever!!
Wonder if that would work on the Cayenne?

 

[Andystocker]

So today was the day the battery 'died' - started at 10am no problem. Drove for 1 hour, had a 1.5 hour meeting, started car no problem, then drove for 1 hour - stopped at a McDonalds drive thru - turned the engine off - ate my big mac and then the car failed to turn over first crank. Second crank usually works - but no - engine did not turn over. Tried a number of times until nothing - dead battery. Called the AA - guy arrived 45 mins later - checked I had oil - sensible and then turned the the key - the engine fired up first time. Chatted to him for a for minuets and then he turned the engine off and on five times in a row. This does not make sense to me at all. The volt meter on the dash sits between 12 and 16 (I think its 16) and he checked and the battery is being charged normally. My garage has never been able to diagnose anything wrong. Really at a loss.

 

[Octane]

So in the end did the AA mechanic say they thought the battery was the root cause? I would expect a decent garage could diagnose this fairly easily.
I suppose the possibilities are:
- the battery will no longer hold charge (failed)
- the battery can hold charge but has been drained (easy to diagnose, hard to fix. Have you got any 3rd party extras fitted, like phone kits etc...)
- the starter motor
- other electrical fault in the starter circuit
in any case there probably should be fault code(s) to give a clue to this. I know you said that you can't normally plug it in, but if you have the opportunity to plug it in somewhere else occasionally you can get one of the CTEK chargers for < £100 and try that.

I took my 958 to a garage in Kent who did a good job fixing a more complex electrical fault if you want a recommendation.

 

[Andystocker]

I've booked the car to the garage - it seems that it might be the starter motor. Quite an big job - engine out apparently! I will update when I get her back.

 

[Graham-S]

The starter motor is under the Coolant pipes in the middle of the V8 under the intake plenum.
Can be a DIY but will take a good 4hrs if you know what your doing

Graham

 

[Andystocker]

Problem Solved!

It turned out to be the starter motor. As the starter motor is located in the V of the block it gets a bit hot after a run and can cause hot start issues. New one fitted and problem solved. If you have a Cayenne and it hesitates when cold - ie it takes a couple of cranks to get her going - then I would suggest that it's a sign that you starter motor is on the way out. I can defiantly notice the difference now - what it should start like and what I had become used to!

Thanks everyone for your comments and advice - I hope this helps other Cayenne drivers out in the future.