So upon swapping my intake manifold as the snow decided to just hail down upon me and jezebel which thanks to an umbrella I was able to keep my engine bay dry. I was about to pull the old manifold out when I noticed there was some oil build up, I was also unable to remove the clip that holds the brake booster vaccum line to the intake manifold. So I reconnected everything due to the snow getting worse and started her up only for the rpm to spike to 6k and throw the code p0300 pending. I erased it and it turns out my pending 507 hasn't returned but the car idles more strongly and the gas pedal is stiffer while I need more force on the brake pedal to stop the car completely. When in park the idle spikes again to 6k, so what in the hell did I do? :l

The p0300 pending hasn't returned and so far the p0507 pending hasn't either, yet the idle continues to be erratic. About the oil build up however does this indicate a head gasket problem? I was thinking of buying a can of head gasket fix to see if that would solve it.

You have a vacuum leak or you kinked the throttle cable.

Some oil in the intake manifold is common. If it bothers you you can install a catch can.

I checked my throttle cable and it appeared fine and not linked but I did have a whim that by pulling the throttle mechanism towards me rather than away as if I were attempting to close an already closed butterfly that it would help. Sure as @!#$ the rampaging 6k dropped to 3k so I tugged on it a few more times and now she's idling at 1-1.2 k but with a pending 507 again however no rpm jumps. So yay. Is it possible my butterfly is damaged or just misaligned? How do I check this?