Lately my wife Exscape has had an idle probelm.
When the vehilce is frist cranked , it has a rough idle ,then when the motor gets to operatinfg temp , it runs fine.
We changed out the idle control valve last week & this helped some.
About a month ago , we had the fuel filter changed because it was bad & needed replacing.
A few month ago [ about mid summer ] , she had a complete tune up done too.
Once the engine heats up to normal operating temp , the car runs fine at all speeds , no misses or hesitation.
We also took the mass air sensor off & cleaned it with spray cleaner.
I'm thinking it might be time to replace the sensor.
I would like some feedback from you guys if there is something else to check ?
Thanks in advance !

 

Any chance that the mass air sensor still has some residue on it from the cleaning? I know that some folks who use K&N filters have a problem with oil from the filter getting on the sensor and causing problems similar to what you have.

 

thanks for your reply, my wife is at the parts store now.
we sprayed it with the cleaner recommended by the part store mgr. [ advanced auto store ]
on the can instructions , it said to let the part completely dry before reinstalling. [ we did ]
at the auto store , my wife had the tech to get a computer read out lean air mix , the print out is at home now.
Right now , my wife just decided to get a new mass air sensor & install it there at the store as we speak.
I am waiting to hear from her in a few minutes & will post the results then.

 

Wow, talk about coincidence! I am a 1st time visitor to this forum... I normally hang out in the 1980-1986 F150 and larger trucks or inline six forums. Please forgive me if I am hijacking [I don't mean to], but I my daughter's 2001 Tribute with 3.0 V6 is having the same problem. It is only when the engine [and ambient temperature] are cold. It will start fine, but then idle very roughly with much "chugging" and will almost die. If nursed through this until the engines warms up and then "happy sailing!"

I took it to a trusted mechanic and no codes were found and the CEL has never come on. The throttle plate and mass air sensor were cleaned and while everything was apart, it was noticed that the rubber elbow for the PCV valve was collapsed, so it was replaced. As luck would have it, the weather moderated for the last week and the problem seemed to be over... yesterday, colder weather and the problem is back.

The vehicle has been well maintained and has ~117,000 miles. Please help. I will gladly "search" if one of you experienced guys will kindly direct me as to what are the best "catch words" or "tags".

Thank you so very much!

 

My wife changed out the mass air flow sensor yesterday & so far , it has ran well.
We have temps that will diip to the low 30's & upper 40"s next week .so we will see then if the problem is fully solved.
It is most noticable when it is cold weather likes the 40"s or lower.

 

Not fully understanding how a Mass Air Flow sensor works [old school / I like carburetors ], why would the MAF sensor funtion differently when exposed to colder temperatures?

 

It regulates the amount of air going into the engine while running.

 

Have you tried cleaning the IAC? I had a 98 Explorer that ran rough in cold temps then it got to the point it wouldn't idle at all. Changed IAC and problem went away.

 

I wouldn't say it regulates the air going into the engine as much as monitors the amount of air.
Did you ever check the connection of the sensor?

 

yes.
I should have cranked it this morning to see how it idled though.
Yesterday was okay, but it was warm outside.
My wife installed the new maf sensor.

 

Try spraying some starting fluid at the lower intake and see if idle changes might be bad gaskets.Mine did that in cool damp mornings idle all over and check engine light would flash as it warmed up it would run good and cel would not blink.

 

I use to suggest using starting fluid for this but was informed that there have been explosions caused by the votile nature of the fluid. They are better off using carb cleaner or throttle body cleaner.

 

Thanks to all for the helpful information and suggestions. It ended up being the gasket at the bottom of the plenum.

 

If you don't mind the residue, you can use WD-40 as a 'enrichment' fluid. It will start lawnmower engines, so is 'burnable'. I think it is a lot less subject to explosions than ether type starting fluids.
tom

 

it is a common problem! the orings on the intake manifold leak air when cold. As engine warms they expand and seal the leak. New orings are the answer. Cheap fix but time consuming to pull intake manifold.
Good Luck!