How do i remove and clean the IAC - 1999 Mercury Grand Marquis

I would clean the throttle body first and the idle air control motor(IAC). Clean where the plate sits and on the back of it/them. You have to remove the IAC to clean it. Brake clean and a toothbrush works fine. If it still is high. Diagnostics need done for the IAC. Most times it is the IAC.

remove and clean the Idle air control (IAC) it may have carbon build up in it. make sure pcv valve is working properly. you can use carb cleaner to clean IAC valve. after IAC is removed, clean at throttle body side also. good-day!

yes get a new one

You need to remove iac valve from the throttle body.The iac valve located on throttle body.Be careful while removing iac valve,its spring loaded, so you dont loose any spring.As the spring may jump out.You will need throttle clearer or you can use electric cleaner or brake cleaner liquid.Its easily available at local auto parts store. ------- For more details about diagrams and how to clean iac valve, click the link below:--- http://whoisbyme.blogspot.com/2011/10/how-to-clean-idle-air-control-valve-on.html ---------- This should help.Thanks.Helpmech.

well, first of all remove from vehicle. most iac have 2 torx screws to remove it. use an old toothbrush or similar to clean it. do not put body of iac in any liquid or it will ruin it. just clean valve on end of iac. also do not push on iac valve, because it will mess up idle of vehicle. just clean the valve on end to remove carbon build up and dirt. you can use brake cleaner or throttle body cleaner for this. it is also a good idea to clean around throttle plate to remove carbon on throttle body itself. but do iac first and put back on throttle body. have a good day!

You'll have to remove the throttle body to replace the idle air control (IAC) valve. First, disconnect the negative ground cable from the battery. Then remove the vacuum line and air duct intake. Then disconnect the IAC and throttle position sensor (TPS) electrical connections. Remove the coolant hoses that are connected to the IAC. Disconnect the throttle cable from the throttle body. Now, remove the 4 bolts that hold the throttle body to the manifold and remove. Be careful with the gasket located between the throttle body and manifold and replace it in the same position. On your clean work surface, turn the throttle body over and remove the 4 phillips head screws holding the IAC to the throttle body. Clean the parts with a dry cloth but do not use solvents on the IAC or TPS. That's it!

Get the IAC valve checked.Remove the Iac valve from the throttle body. It is on the side facing the front higher than the tps sensor. It has a 4 wire connector. Make sure this is clean. If it is dirty/dusty then clean it. This valve controls the idle speed. After cleaning it turn the ignition on with the engine off. The Iac should move in and out to find the stops. If it does not move you have either bad wiring, Iac or pcm. Most likely is Iac.
-------- For safety measures,before removing the IAC make sure you don't have any vacuum hoses unplugged. Next make sure the throttle blade closes all the way.Iac is short for idle air control valve. ------- Thanks.Helpmech.

its located on the throttle body connected to your air intake manifold where your throttle cable connects on the throttle body there is a adjustment screw connected there

possible vacuum leak into the manifold (inlet) or dirty iac causing it to stick remove and clean if this improves it renew the iac as cleaning never works for very long. if a K&N air filter is used remove it is bad for oxygen sensor, catalyst and iac as oil residue from filter can build up in iac causing it to stick. If none of these help check voltage to iac and feel for clicking when ignition is turned on and off .

Ok, this is what I did a few months ago and my '03 Olds hasn't stalled since. Buy GM cleaner P/N 1052626 or GM X 66A or equivalent. Locate the Idle Air Control Valve (IAC). On the front of the throttle body you'll see a shot-glass-sized metal cylinder with a black 3 wire connector. This metal cylinder is just to the right of a rubber air line with a 90 degree elbow on it, this is the IAC. Removal: 1. With the car in park and the ignition OFF. Remove the electrical connector from the IAC. 2. Remove the 2 IAC attaching screws. 3. Remove the IAC from the throttle body. 4. Remove the IAC O-ring. NOTE: If the IAC has been in service: DO NOT push or pull on the IAC pintle. The force required to move the pintle may damage the threads on the worm drive. Also, DO NOT soak the IAC in any liquid cleaner or solvent, this may damage it. Cleaning: 1. Using the cleaner, clean the IAC valve O-ring sealing surface, the pintle valve seat, and the air passage. I used the cleaner, shop towel, and a tooth brush. * If the air passage has heavy deposits, remove the throttle body for complete cleaning. * Shiny spots on the pintle seat are normal and do not indicate misalignment or a bent pintle shaft. 2. Inspect the IAC valve O-ring for cuts, cracks, or distortion and replace if damaged. NOTE: The IAC may be damaged if installed with the cone (pintle) extended more than 28mm (1 1/8in). Measure the distance that the valve is extended before installing a new valve. The distance from the IAC motor housing to the end of the pintle should be less than 28mm. Manually compress the pintle until the extension is less than 28mm. Install: 1. Install the IAC into the throttle body. 2. Install the 2 IAC attaching screws and torque to 27 lbs. 3. Install the electrical connector into the IAC. 4. The powertrain control module (PCM) will reset the IAC whenever the ignition is turned ON. 5. Turn the ignition ON. 6. Turn the ignition OFF. 6. Perform the IAC learn procedure. IAC Learn Procedure: 1. Start and idle the engine for 15 seconds. 2. Turn the ignition switch to the LOCK/OFF position. 3. Wait 15 seconds. 4. Restart the engine and check for proper idle operation. Hope this works for you too.