So I'm having a weak start issue. Took my car to advance auto and they checked the starter, battery, and alternator. Everything checked out good but my question is. My red top is rated at 720 CCA. But when they measured it, it was only putting out 639 CCA. Which I think should be strong enough to start my car. I mean it does start the car it's just slow like the battery is almost dead. Anyone know what might be my weak starting problem??

 

Check for a parasitic drain.

 

no parasitic drain. starting to think this battery is just crap. gonna switch it out with my truck battery tomorrow and see how that goes

 

Yellow top has more starting power. Red has better sustaining (amp/stereo/lighting) capability.

 

got that flip flopped amigo. Yellow top is or high amp loads and Red top is for CCA

 

Lets keep in mind the starting trifecta. Battery - alternator - starter. Battery could be going out or have a bad cell if voltage significantly drops at startup. However, low battery voltage could be due to bad or failing alternator. That should be checked. Additionally, a faulty and dragging starter will create an added drain on the battery and charging system.

I've always found it fascinating how a problem in just one of these areas can cause problems, damage, or symptoms for another. So, properly investigate all three components.