What is the best starter replacement for 2010 C6? ( When car sits for a day or so, there is a hesitation when starting. Once car has been run, it starts immediately. Any ideas?)
Thanks!

 

What do you mean by "hesitation" ??...push the button and nothing happens or it cranks a little before it starts ??...always best to get your battery tested before throwing parts at it.

 

Cranks a little, then starts. If it is the starter, what do you suggest as replacement?
Thanks!

 

It doesn’t sound like a starter because you said it “cranks a little”…I’d check fuel pressure or a cam or crank sensor.

 

Sounds like a fuel pressure problem at the rail (bleed down when not run for a while) with an after market pump in play.
Quick down and dirty is to change the pre pump time in the tune, so it primes the rail a little longer, before the engine cranks.

In HP tuner, fuel system, fuel pump, primer time, and change that from 2 to around 3 or 4 seconds.
This will have the pump priming the rail for an extra second or two to get the rail back up to pressure when the car sites for a while and the rail bleeds down, before the starter goes to crank the engine. The only down side, is once you press the starter button, have to wait the extra second or two before the starter does go to crank.
So start with 3 second, and if you still have problems, push that to 4 seconds.

If this is a stock motor with no tune on it, then you have a problem with the fuel pump bleeding down to quickly/taking more than 2 seconds of prime to bring the rail pressure to correct pressure, and it may be time to replace the pump. The primer time tweak will still work, but not worth the $500 is going to cost you to either by HP tuner for the car, or pay a tuner to do this instead.