2001 Mercury Marqui. I just replaced the intake manifold. Started it up and idles great. When driving it upon acceleration the temp gauges goes up and down with a beep and has slow uneven acceleration. Once it get to speed everything works perfect. I am lost.
Don't drive it, pull the manifold and replace the gasket. Scrape surfaces clean first. Look for signs of leakage between the water jacket and the intake ports.Be very careful. Change your oil just to be safe.
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