I just bought a 88 bronco 11 from a friend . He sayed it runs well but of course it needed 3 frost plugs to start with and valve cover gaskets and who knows whats next? So i have changed out the frost plugs ,what a job that was thank god for that 90deg frost plug installer.The cooling sys seems to be in good shape new hoses,belts and so on. Fixed the valvecover gaskets and now i have to work out why it fires up then runs good for about 15mins then stops like someone turned the key off.The tfi-iv ignition module is new and all wireing looks in good shape. anyone have any ideas on the problem? This is my second bronco11 i have owned over the years the first one was great .