Cold Kranking Amps

[droppedlexus]

this seems strange to me, I own a 1993 gs300 and a 1998 gs400.....both cars seem to do the same thing......2 years ago I went to purchase a battery for my gs300 the sale person at the auto parts store stated I needed a battery with a high amount of cold cranking amps, well I decided to go against him and brought a battery that was cheaper and was about 15 cold cranking amps below his suggestion.....well winter came and my car sat for 2 days and when I went to start it the car turned on but was idle was very rough, I mean shaking rough! Recenlty I purchase a battery for my gs400, another battery just below cranking amps, and winter came and bam my gs400 starts up rough, I throw a battery in with enough CCA and car starts a little rough but now is fine??????

[TurboGS300]

One has nothing to do with the other <_< The car is running rough because of other reasons, not the CCA of the battery.

[deadmilenko]

Cold Cranking Amps is a rating used in the battery industry to define a battery's ability to start an engine in cold temperatures. Not keep it running after it has been started. The rating is the number of amps a new, fully charged battery can deliver at 0° Fahrenheit for 30 seconds, while maintaining a voltage of at least 7.2 volts, for a 12 volt battery. The higher the CCA rating, the greater the starting power of the battery. Once the car is started the CCA have nothing to do with the engine at rough idle. What grade and kind of oil are you using and what was the temp outside when this happened? These may have an impact as well.