rough idle

Hello,
I have been nursing my windstar along by adding fuel injector cleaner to it about every other gas tank. That has helped the rough idle probem until recently. When the car comes to a complete stop the engine trys to stall out and the idle speed drops to about 5000 rpm momentarily before returning to almost normal idle speed, some times, but rarely the car stalls out completely. Other times the car hessitates while driving at a constant speed. So I changed the spark plugs and wires but the problem still persists. The Check engine light is on constantly and while driving the vehicle it sometimes blinks more than 100 times before staying on. Any suggestions?
Chieko

I would start by replacing the Idle Air Control motor (IAC). What you describe are classic symptoms of a bad/failing IAC.

It may not solve ALL of your concerns, as sticking IMRCs can also lead to these symptoms, but it's not AS common, and it is more $$.

Thanks for the advice, It defintly helped. The car idles much better now. The check engine light is still on and blinks intermittently. I guess I'll go to Autozone to find out what code is being returned before spending any more $$.
Thanks for the advice.
Chieko

A blinking CEL indicates that conditions exist that are damaging to the catalytic converters. Usually this is raw fuel being pumped in the exhaust perhaps due to a misfire.

In any event one cannot ignore a blinking CEL. Get it checked out and repaired ASAP before it damages the catalytic converters. The cats are big bucks.