I have a '96 camry, 145K miles with a stalling problem that's getting worse. It'll stall when stopping after high-speed driving. I noticed a lot of info here about stalling problems and started looking into things last night. One thing i did notice was oil on the #1 spark plug. It was on the ceramic part, like the oil was poured in through the wire boot. Is this a leaky valve cover gasket?? How much $ would this cost to fix? Would/could this cause the stalling? TIA