flashing check engine light might be a misfire. how old are the spark plugs in miles / years?
miles on the car?
are the battery terminals locked down 100%,...it is easy to spin them on what feels as tight and not actually get a good contact with the battery.
at only 7-8 years I would hope the terminal ends and their bolts are still physically good,... ...but such may need to be swapped out. as they are borderline going bad and letting the car run like crap,...but run.
___
occasionally people here get bad batteries new,...(defective).
miles on the car?
are the battery terminals locked down 100%,...it is easy to spin them on what feels as tight and not actually get a good contact with the battery.
at only 7-8 years I would hope the terminal ends and their bolts are still physically good,... ...but such may need to be swapped out. as they are borderline going bad and letting the car run like crap,...but run.
___
occasionally people here get bad batteries new,...(defective).