My car idles at 2000 rpm when it starts foor about 2 mins before idleing back down when I stop at light or stop anywhere it idles 2000 again I just replaced headgaskets all fluids and had heads checked and shaved . Car overheated 16 month ago was parked when I took car to be repaired it idled correctly but now runs as above

SOURCE: car revs up whilst stopped, idle problems

you need a new oxygen sensor

SOURCE: My 2002 Ford Taurus will shutter and die when

the idle air control valve is responsible for engine idle.
this is a common failure on ford's. but I don't think yours is bad because it does idle high befor it dies.
you stated you had codes p0171 and p0174 these are lean codes for bank one and two, you said you found a vacuum leak and repaired it, the vacuum leak was mostly likely the cause of the lean codes, however the pcm has calibrated the fueling stategy for this lean mixture, what you need to do is erase the KAM "keep alive memory" this is done by unhooking the negative battery cable for 60 seconds, this is the only way to erase the KAM the $6000.00 machine I use wont even do it.

once the KAM is clean the computer will go into a relearn state and all operating values will be adjusted for the vehicles current condition, during this relearn session the vehicle may have some driveability issues (low or high idle, stalling, poor fuel economy) the relearn should complete within 10 minutes of idling and then 10 minutes of driving.

good luck and keep me updated

[email protected]

SOURCE: my car keeps overheating while it is idling.

If it's only happening while sitting at a stop light and idling, the problem is probably in the cooling fans. Turn your A/C on high and pop the hood. Check your cooling fans to see if they're running. If they aren't running, it's the fan relay. In my 99 Taurus, the high speed fan relay is located in a slim black box next to the battery, it's the large square relay right up front. Use a known working relay of the same size and pop it into this relay. If the fans turn on, there's your problem. Replace the relay. Try the same with the A/C on low, but this relay is in the power distribution box (number 31). The 2002 may have a CCRM (Constant Control Relay Module). The CCRM is an expensive part (over $100.00). You'll be able to tell because the CCRM is a very large box that is mounted next to the battery and contains relays that are not replacable. It'll have a part number followed by a large letter/number. You'll need this part number and large letter/number to order the new.