2008 GTS Slow crank

[Streetsmarts]

Guys,

I have a 2008 GTS with 55k miles on it. For the past couple of months the GTS generally cranks slowly but starts up on the first try when the engine is cold or has been sitting idle for a couple of days. But when the engine is hot, it take 2 tries to get it started up.

With a hot engine it could take up to 4 or 5 cranks to get it started. Last night i was out and about and stopped by the grocery store and 15 mins later it wouldn't start up. Waited about 2 hrs hoping it would start up on a cool engine but it didn't. i got desperate and decided to Jump start it with another car battery connected to it and it started right up. I drove it straight home, when i got home i tried to start it up, it will slow crank as usual but wouldn't start up. This morning i crank and it started right up.

I'm confused...it cant be the battery, i doubt its a starter issue cuz it shouldnt crank at all if the starter was bad ....any suggestions guys?

[omolddesign]

Why can't it be the battery?

[Doug_B_928]

If the battery is good, then it sounds like the Battery/Starter/Alternator cable.  Search for that to see others' descriptions of the symptoms etc. and see my write-up in the 997 DIY section for the fix.

[Streetsmarts]

The battery is good. I actually read your write up and I suspect it's the battery/ starter/ alternator cable that needs to be replaced but I can only find replacement cables for 997. Can anyone help with a part number for a cayenne?

[Doug_B_928]

Ooops, I missed which subforum you were in (thought it was a 997).  I haven't heard of this on a Cayenne but I'm sure others much more knowledgable than myself will chime in.  Thinking out loud, I recall reading that some model Cayenne's have two batteries...

[wvicary]

Sounds like a battery fault. How did you test the battery to determine it's good? The early production first generation had a problem with the alternator cable, your vehicle doesn't suffer from that issue.

[Fmscell]

Sounds like you verified the problem when you boosted it. I'd say it's a battery, but you'll need a multimeter to measure the voltage drop when cranking