I have a 2000 Mercury Marquis and often in the morning it barely runs for two or three minutes. Requires several restarts. Once it runs a bit all clears up and car runs fine. Car has about 66000 miles. It does not turn on any error lights - it just runs rough.
Just a little bit ago I tried starting the car but it seemed to not want to go at all. After about a dozen attempts and many restarts it finally decided to go.
Any help appreciated
I guess I could go spend a couple hundred at the Ford house and get it analyzed better, but my budget is sort of limited.
Probably the idle air control valve. I'll paste a post from 02 with a picture from my 4.6. I drew an egg shaped circle on it and added a line from nowhere in particular to the bottom bolt.
THE IDLE CONTROL VALVE Submitted by pro-five-oh / 10-23-02
Having a funny idle problem? Already did a normal tune up with fresh spark plugs, PCV, fuel filter, cap/rotor and maybe even new spark plug wires? Did you run a code scanner and got nothing? It is time to clean the idle control valve.
Depending on whom you talk to, this little gadget is called the ISC, BYP, IAB or IAC valve. Whatever you call it, the valve goes bad due to a broken motor or soot buildup from crankcase vapors. The answer is to clean the assembly or, if all else fails, replace the motor attached to the unit with a fresh one.
-------------------------------------------------------------------------------- Where is it?
On EEC-IV multi-port EFI motors, the idle control valve is located on the throttlebody. The valve has a cylindrical shape with a small wiring harness at one end, with another casting that attaches to the throttlebody.
There are two 5/16th bolts holding the valve to the throttlebody. Disconnect the harness with a small flathead screwdriver and unbolt the valve. Check the gasket that attaches the valve to the throttlebody for any damage or cracks, and replace if necessary.
With the valve in your hand, generously spray light oil such as WD-40, or a throttlebody/carb cleaner in the two bores of the valve. Shake the valve around to ensure the cleaner is moving freely in the bore. If possible, get a length of fuzzy pipe cleaner and use it to scrub the bores to a shine.
Shake the valve until most of the fluid is expelled. Repeat the above procedure if the expelled fluid is extremely dirty. Reattach the gasket, the valve and its wiring harness. You should see a dramatic difference in the idle control of the car.
Thanks - your information was spot-on. Also, the photo was worth a thousand words. The part is $50 at the parts place, but I ran into the old situation of "our computer says we have it but I can't find it". It will be available leter this afternoon. Thanks again, Ted S.
Glad to be able to help. As you can see, I passed along help given here by another. I've yet to replace mine (166k) because the cleaning suggestions worked so well.
Another chapter on the air valve - if you can lend an ear for a moment.
I took the valve to my local shade mechanic and after a while he said the valve was the wrong part. I go back to the parts house, but get the same answer - "there is inly one part". I finally rounded up some tools and took the valve off myself and - yes - they seem to be different. My original had a connection to a half inch air pipe which the new one did not have. I just ignored the pipe and installed the new part and engine idled nearly like it should. It's too slow and tends to die, but it doesn't run rough any longer.
Question is - - DOES THE VALVE CONTROL IDLE SPEED? I may have to spring for the real Ford part ( $100 ) after all.
I am really tired of all the troubles replacing a simple valve. Every step requird at least one 45 mile trip. Maybe I'll go shopping for a 66 model pickup.
You're way ahead of the game if you avoid the dealer costs for exchanging this simple part. I can't answer your question but since you have the old one off why not try the cleaning that was described in my first response. I've done mine three times (so far). If you look inside you can see a little shaft and spring. They get a little coated and that makes the shaft stick. WD-40 works well but anything you have would be OK. I always leave a film of lubricant on it before reinstalling.
In the replacement valve I do see the shaft with the spring, but in the old original there's not much to see and nothing that appears cleanable. Maybe I'll spray some carb cleaner in there.
That's the idea. Then shake it, if you have air blow it out. Doesn't take much and the process of removal and replace is quick. If it works (should) maybe you can return the other one. If you have WD40 good. If not try something else (not heavy) before reinstalling.
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