Does a new iac valve need to be adjusted before installing in a 2000 mitsubishi galant ES 2.4L

left side of car, in the truck, below carpet

Sometimes you can clear cars computer by taking off battery cable,maybe it will work for you, leave battery cable off about 10 mins. and try that. Just a fast thought, Hope it works for you. Billy Wyatt

Fig. The IAC motor is usually mounted on the throttle body (click over image for zoom)

1. Disconnect the negative battery cable.
   
2. Remove the air cleaner intake hose.
   
3. Remove any necessary hoses from the IAC motor.
   
4. Detach the electrical connectors from the IAC motor.
   
5. Remove the retaining bolts and remove the IAC from the throttle body.
   
6. The installation is the reverse of removal. Replace the IAC gasket.

Hope helps (rememer to rate and commet this answer)..

Code P0505 is a problem with the IAC (idle air control) which regulates the idle speed. To check it quickly, disconnect the IAC connection located below the throttle body near the firewall. Start the car and the idle should run around 1300 rpm at idle. If this is the case then the likely cause it a bad idle motor. The cost of a new one is $110 at Pep Boys or $30 at a Pick n Pull. Keep me posted, thx.

You would have to have a fuel pressure gauge or install a gauge for it which isn't a bad idea.

Sounds like you might have an idle problem like with an IAC sensor, throttle position sensor or you may have a bad vapor/liquid separator valve in your tank. Is the tank mostly full when this happens? 

You have to pull the spark plug boots out of the valve cover and use a long extension with a spark plug socket and remove them.

Try this web site for info on Mits Galants http://www.thegalantcenter.net/forum.php

Idling problems may be cause buy a number of issues.  You may check out the fast idle control valve and PCV if they would need cleaning.  You can check out the timing it may be advanced, that is why you feel that the car runs hard.

do you have spark? How do you know if your timing belt is good? sometimes it doesnt break just shed the teeth which could be missing under the crankshaft. The best way to check is to have two people. have one try to start the car and see if the camshaft is actually spinning. The crankshaft will always turn but if the teeth are gone on timing belt this would cause the belt to stay in one position not moving the camshaft. so if you can remove the upper timing belt cover and do this quick inspection with someone that will tell you for sure. if it does look like it is spinning then by hand turn engine very slowly with plug coil wires removed. and make sure teeth are all there. It couldve jumped timing. (valve timing)