Starter Relay? Second Problem?
So, It started a couple nights ago when my car decided not to start, the headlights came on, stereo came on, all gauges light up and I turn the key and nothing. Well after about 20 minutes the car started. The next day I go to autozone to get a free replacement battery. They test it out, battery is good, alternator is good, load test and everything. I go to start the car and everything turns on. Nope. car doesn't even make the starter noise. New battery is now in and charged up. So, I go under the hood and pull the starter relay. I replace this with a fan relay of the same size and amperage and instantly the car starts. So I purchase a relay inside and put it where the old fan one was. Car starts fine, 7 times or more. I go to start it last night. Same old song and dance, no turning over. I put the brand new relay now in the spot. Starts and I drive the car 100 miles no problems. This morning the car starts and while on the freeway, 80 mph I give the car throttle to pass (rural highway) and the service engine soon light starts flashing. I pull over and shut the car off, turn it back on and it's all good. But i feel like i've lost 2 cylinders. I finish driving (luckily 30 miles) go home and go to start the car. Same crap. switch the relay AGAIN. starts, but still feels like crap, no SES light. Get the car checked at autozone, no codes. Where do I go from here? Thank you for trying to help.