Coming home last night, the car lost acceleration while I was doing about 50 mph. The harder I pushed the accelerator, the slower it got, but letting off the gas, the car idles well. I pulled over to let traffic by and only had to go about 4 miles to get home, but only by barely idling and shifting up to 4th gear as the car gained speed to about 20 mph.
This morning, I opened the hood and saw nothing strange. I started it up and it idled fine. When I hit the gas, it makes a whoosh sound with some grrr added in. If I hold the gas down, the car's idle will pulse between 1600 to 1800 rpm.
No check engine light came on. It had a new muffler/resonator/catalytic system put in March. I've been getting a little trouble with the power steering pump squealing and balking when making from stop turns.
Plugs wires seem fine - pulled one while it was running and it was very noticeable and had a long spark.
Car has 240 K miles on it and deserves a rest, I know. Any ideas what the problem is? Would this have a ceramic catalytic converter that could break and limit air flow?
TIA