2003 Pontiac Grand Prix GT 3.8 NA
Was sitting in stop-and-go traffic and tried to accelerate. The engine sounded like it was drowning and was not accelerating much at all, and I heard someone else say, "what's that smell??!"
Check engine code is telling me Multiple Misfires, so I pulled and tested the coil packs, they're fine. Changed the plugs and wires, and it's still doing it. Once up to speed I can stay up to speed, but it accelerates very slowly. The car is also burning through about 1/4 tank of gas a day. There's a slight squeal in the engine, like a belt squeal, when I accelerate from a stop, but after the car gets going faster than 10-15 MPH the squeal stops. Car leaks oil and engine coolant, but not a lot (could be unrelated) and I can't see from where. Radiator has some brown gunk on the cap and in the tube (probably also unrelated). The engine does not overheat. Prior to the issues, I had a check engine light for the rear O2 sensor, never got around to replacing it. I had my fiancee following me while limping home, she said my car smelt horrible. I smelt something like a slight burning of rubber, and she said the car smelt a little rotten, but also like burning.
Plugs and wires usually solve this issue, however, they did not. Now I'm lost. Any ideas?