Engine misfire? Code 0300

[9999]

Hey

I just bought my camaro a few days ago, and the SES light has been on. Today I went to autozone to pull the codes expecting an o2 sensor problem (because when I bought the car, there was a new o2 sensor in the trunk) but they told me it had a "random engine misfire" problem.
I bought 3 new ignition coils and replaced them all, the previous owner said he just changed the spark plugs and wires. I pulled one of the spark plugs and verified that it looked new.
I got the guy at Autozone to reset the codes, so I went home and changed the coils and drove it around without the light coming back on.
Later tonight I was driving again and the light came back on.

A common answer I found when searching, was that the cat could be the problem, but I have no rotten egg smell, and
I think its important to mention it does not feel like the car is "constipated" or bogging, to me it feels and drives exactly like it should. Also, I never hear or feel any of the engine misfires.

Also, I am new to driving a standard but now I've pretty much got the hang of it, but I dont know if mess ups could cause the readings.

If you have any other ideas I'd appreciate it, and would driving my car like this risk any damage?

Thanks a lot

Oh and there are 91k miles on the car

[jackmalone2001]

Hello and welcome!!

Your random misfire problem could have been solved by your new coils or o2 sensors install. Take your car back to Autozone and have them re-run the codes. It could be anything from a malfunctioning EGR valve (especially if you are new to manual tranny's) to a busted vaccuum hose. Your best bet is to re-run those codes, and start from scratch, that way you are not barking up the wrong VERY complicated tree.

Good luck!

[9999]

I put in the coils two nights ago, then today I put in new plugs and wires and the problem is still there.

An o2 sensor would make sense since there was a new one in the trunk when I bought my car, but do they commonly cause misfires?

Ill bring it back to autozone to see if its still throwing out the same code.

Thanks

[corning_d3]

I've bought the cheap brand coils and had a few of them bad, but that doesn't sound like your problem. I'm thinking EGR, maybe.. Does it idle rough?