My '91 Toyota Corolla with 118K miles has a problem that cropped up last night. There is a VERY prounonced vibration when I accelerate quickly. It increases from 0-30mph, then sort of tapers off. When I am cruising at 50-60 mph, I can sometimes feel it. At these speeds, the engine feels like it’s revving up slightly then returning to normal. If I accelerate from 0 rather slowly, it is barely perceptible, if at all.
I also notice that the car seems slightly sluggish as I accelerate, but this improves at about 50 mph or so. When in park or neutral, I can rev it to my hearts content and it sounds pretty normal.
I used one of those isopropyl alcohol additives in my gas tank when I last filled up and I currently have about 1/4 tank left. Any ideas?
p.s. Please don’t say it sounds like the transmission, because I’m pretty broke.