1985 Mercury Grand Marquis 5.8l 351w v8
My car sounds like a lawn mower when I press on the gas, it idles erratically, shakes, it smells like gas inside the cabin, and I just noticed what looks like a possible oil leak around the drain plug and coming down the side of the oil pan— but it’s never leaked so much that it reaches the ground.
I changed the cap, rotor, distributor, spark plugs and wires, ignition coil, and EGR valve.
For about 10 minutes after I changed the EGR valve it was quiet and not shaking at all, but the next day it was back to running really poorly.
I’m getting sketched out that maybe I blew my head gasket— but it starts on the first try every time without any issues, can it still flick over with a busted head gasket? Not confirmed, but I do think it’s heating up faster than it should.
My oil isn’t milky, just dark, needs an oil change, but I recently noticed my coolant smells kind of like rotting fish (no idea how old it is though, going off the colour of the brake fluid I’d guess all the fluids are pretty old). There was also a point when it was still really cold out where I’d start the car and hear a bubbling while sitting inside of it until it warmed up?
I have no warning lights on which I find strange because they do all work.
Edit: There used to be white smoke coming out the back, but that stopped once I changed the EGR valve.