2001 Gen1 with 165K miles but probably applicable to high mile Gen2. Engine misfiring (bucking at low speed) with loss of performance. Very intermittent at first, increasing over time. Turns out that valve cover gasket gasket leaks oil into spark plug tube which shorts the spark to ground. Simple fix. I was pressed for time with my day job so let Toyota do it for $300. Regards
Thanks for the info and heads-up; was the PCV valve replaced also? I think that the black rubber valve cover gasket is relatively high quality; the top of it has a molded ridge that fits into the valve cover to hold the gasket in place.
Oil in the plug wells will do that. I replace my SHO's gasket everytime I check and adjust shim clearance. At 160K, your gasket did its job. It was really time for it to be replaced. Glad you had that straightened out. Drive safe.
What does "SHO" stand for when replacing the gasket? Thanks, sorry if it's a "not so obvious" question.....lol
I think @N3FOL was talking about another car than a Prius... probably a Ford Taurus SHO. Basically, take a somewhat boring Ford sedan and stick an engine with about twice as much power in it, to make an interesting Ford sedan.
