Contour Enthusiasts Group Archives Forums General Troubleshooting bad missing/stumbling...over 3000 rpm and COLD it runs fine

I had a similar problem with my 2.5 -also got bad after a "good wash". Turned out to be leaking UIM gaskets. They're figure8 shaped o-rings between upper and lower intake manifold that eventually deteriorate with fuel, oil, and heat changes. Check by spraying WD40 at mating surfaces of upper and lower intake manifold -the WD40 temporarily "seals" the gaskets and ur low-speed will smooth out. Not a difficult job to replace, & gives U a chance to clean all the EGR and intake passages as well!
Good Luck.
Ed

New Plugs fixed it. Runs smooth and revs great!! The Motorcraft AGSF32 PPM are the way to go.....if you can find them. I have NEVER had a car so plug sensitive! I will keep this car a little while longer UPS should have my FMS wire set here today? I hope.

Thanks for the help
Louie