code p0308

Hello I have a P0308 code that has popped up for a few weeks now. Also have a bad tick coming through the exhaust. I’ve replaced spark plugs, checked coil packs, checked injectors, checked the intake for stuck or broken valve rail, checked for broken or worn wires and I did a compression test...

just posting this to see if anyone has had the same issue. have a code p0308 and p0019. car has a chopping sound like it cammed lol and rpms will drop to 500 and then shoot up to 850 during idle. if anyone has any info on it that’d be great. i have no rush to take it the a shop so id figure id...