ok so the wife drives a 1999 Ford Taurus. It has the 3.0 DHC v-6. Motor runs sweet all day long except for when we go to start it in the morning. When we turn the key the motor instantly jumps to 2500-3000 rpms and with in about 35 seconds or so slowly revs back down to idle speed. I really was thinking IAC valve so I changed it. Fixed problem for all of 2 days now right back to same thing. Car is sowing no check engine light. Also Im smelling a very rich smell when it first starts. Smells just like when you do a fuel system clean. I cant find ANY vacum leaks, oils not gasy smelling. You think maybe intake gasket leak somewhere????? im stumped.
probley one on the intakes leaking prety sure it has plastic intakes
Plastic upper, yamaha engine, very good engines, check the egr, they are touchy engines but last forever
intake is aluminum but im taking it in to have a leak down test to make sure. she rattles pretty good now at start up from it reving so high everytime.