^ Does Forscan work on OBD1 vehicles?
Oh I did check the codes, the problem was the mechanic who could never fix anything.
I had the new truck's battery checked today at an auto parts store. It's a 850 cca battery reading at 83%. I didn't check the manufacture date, but at 83% do you think it's due to be replaced? The guy said they didn't have any batteries the right size with higher cold cranking amps, and he suggested an AGM (gel) battery from another store. He said it would have numerically lower cca but would perform much better. I don't know anything about batteries, so I guess my options are get a new lead battery with 850 cca that's running at 100% instead of 83%, get an AGM battery with lower cca that hopefully will perform better, or just take it back to Car Max and drive a loaner until they can figure something out.
Woah wait a minute there! "I did check the codes", but, what codes did it set? This is usually a primary piece of info, more important than anything else you've stated so far. If the check engine light comes on, it will set a readable code.
I don't know if an 850CCA battery is stock for a Sport, "maybe" especially considering it may be a group 65 which lower trim models didn't receive, lower trim even received a smaller battery group for a while, but it is not clear cut whether 83% means needs replaced or not.
You shouldn't expect one with higher CCA, 850 is a premium group 65 battery. largest size that will reasonable fit and plenty with battery in good condition and charge state, but, the question is whether it's at only 83% because of poor charge, or excessive discharge, or worn out battery and yet, if it is at 83% due to only being worn, that's plenty to get you through summer months and only in the colder winter climates would be a problem in winter.
Rather than a % #, the readings would have been more useful, just as check engine light isn't as useful as the code that set it. Details.
If it did not come with an AGM battery, you don't need AGM even if the battery is bad (which is indeterminate at this point, just a new battery. It will not "perform much better", but it will last a few more years if it is the only problem (being bad battery) but a waste of money if some other problem is draining the battery excessively. If the current or original battery was not agm then I would reject all his statements as nonsense.
Let's back up a bit. This is not so complicated. When the vehicle is running and the malfunction is observed, use a multimeter to measure the electrical system voltage. If it is near, even a little bit below 12.0V, it is not the battery, but if it is not up closer to 14V with the engine-off state battery reading 12.0V or below, it may be the charging system, and yet the newer setups disable much charging if just idling till the battery voltage drops too low so I do mean an already below 12.6V battery.
It is possible there was an existing fault and this was why it was sold to carmax, and regardless of any of the above they should make it right as long as they are obligated to, whether this entails replacing the battery or something more - it is not your problem/expense/burden yet, except to make them hold to what they promised contractually.
I would not buy a new battery given the present obligation by carmax, if it is the battery, or the charging system, or whatever, it's their burden to fix. You might suggest to them that a mechanic (or whoever tested, I wouldn't lie but I wouldn't screw myself over about this either), determined that the battery capacity was lower than ideal, and maybe they put a new battery in and it fixes, it, or maybe it doesn't but you drive and pay attention and if the problem comes up within the repair window of 30 days, they keep working to fix it and you get a new battery out of it as a bonus, but be sure that being a sport with a 850CCA battery, they don't swap in something sub-par with lower CCA, I mean 750CCA or more could be due to variances with suppliers but below that is substituting a lower quality battery and is unacceptable, as long as you do the research to find what the factory battery CCA is, they only have to match that, or come close if being reasonable... it really doesn't need 850CCA but if much below that, the lifetime of the battery may be compromised so might as well hold them to what the vehicle should have had in it.
Haha, now I'm just rambling. Make them fix it until it becomes your burden to do so and then, either DIY or if taking it to someone, don't take it to someone who suggests some special more powerful battery, with stock parts it should work fine, unless you have a specific reason to change from stock. FYI the best value group 65 batteries for it are the upper tier from Costco or Walmart, which are about 850CCA and around $100, maybe a little more due to covid.
