996 starting problems

[50something]

Any help or advice much appreciated. Car turns fine and starts from cold but when warm after several miles and turn engine off it will not start on first just, just nothing. Then as you try again it starts to try and then after next turn it fires up.
I have put in a new Bosch 80a battery and leave on trickle charger when not using. Local Indy thinks earthing but not sure.

[e12mat]

Either earth strap or the +ve cable. Both increase resistance and thus higher voltage drop when they're hot.

My 997 turbo had to have the engine out recently and they noticed the earth cable looked below par, the difference it has made to the cranking when hot is staggering.

[50something]

Thanks for ideas, is it a diy job to find and sort or best done by garage?

[e12mat]

A good way to check is to use a voltmeter.

Measure battery voltage with engine running but cold and also measure at the alternator output. This will give you an idea of the voltage drop.

Next when you've been for a run and the engine is nice and hot, measure at both points again. If it is cable heat related you should see a reasonable difference in the delta.

In terms of changing it, I'm not massively familiar with the 996. However on the 997 non turbo I think the cable snakes around the engine and it would take a very competent Diy mechanic to change.