Regarding the pipe from the left side of the engine. I assume you are referring to the side closest to the passenger side of the car. If so that is the exhaust manifold and a pipe which you can see connected directly to it from the passenger side biforcates leading to the catalytic converter. I have an '86 that has 3 pea sized holes on the top which I found by raising the car and listening then feeling the air escape. The holes are on the top of the pipe and cause a loud ride which can be heard from inside of the car. I am in the process of repairing this problem. If you decide to raise your car and check this out use extreme caution!!!! Good luck :>)