air intake control valve

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my 1991 Mercury Grand Marquis 5.0L starts, then sputters out. i tried cleaning AICV, and it worked to an extent...bought and installed new one and car runs much better, although i think maybe a tad too fast at idle now. does car have to reset itself? is thuis normal?
 
Yes, they have to reset. A few start/stops of the engine should be all it needs.
But also clean the throttle body bore and plate out real nice. They go hand in hand. Idling anomalies and dirty TBs go together.
 
Maybe disconnecting battery for a while can speed up the process of idle relearn. Usually older vehicles clear out with a battery disconnect.
 
Originally Posted By: beast3300
Maybe disconnecting battery for a while can speed up the process of idle relearn. Usually older vehicles clear out with a battery disconnect.
+1 this is what needs to be done to reset the pcm , disconnect the negative terminal for 1 hour and then hook it back up and it will good to go
 
Warm the car to op temp. Disconnect battery. Get some coffee, let car set 5 minutes. Make sure AC is off.

Reconnect batt. Start car. Let idle stabilize, Foot on brake, shift through all gears, pause 5 seconds in each/let idle stabilize in each gear. Put back in "park". Turn AC on, fan on high so it doesn't cycle, repeat process of going through the gears.

The above assumes you did not mess with your base idle/adjust idle hard stop. If you did, unplug IAC, adjust idle speed to spec listed on the emission decal, then go through the above.
 
it worked!!!!!!! i ran car, then got home, disconnected negative/battery for 20 mins. started her up and she isn't racing anymore!!!!

THANKYOU VERY MUCH!!!!!
 
It will relearn the same if you disconnect the battery or not.
It just starts from a different place to relearn.
Disconnecting the battery will clear codes.
Normally, things are initially WORSE after a disconnect.
But hey.. it got to a good place! That's what matters.
 
car tune up is complete. new sparks, fuel filter etc. car runs like it was new! i appreciate all the help I recieved on this site! thanks
 
i changed TB sensor, AICV, and spark plugs, and fuel filter. oil change coming up:) this 1991 mercury is super smoothe. idles like new. am having fun with it
 
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