Contour Enthusiasts Group Archives Forums General Troubleshooting Low idle, sometimes stalls

I did a little research on this and found some things that may cause the car to idle very low and stall like a vacuum leak or iac needing to be cleaned. I am curious if this would cause the cel to come on?

Here is my situation:

for a couple days it would idle very irratically, bogging down to 250 - 500 rpm then it would shoot up to 2000. a couple days later it started stalling out when it would bog way down. Now it just idles really low like between 400 - 500 rpm and doesnt stall out or rev way up on its own. The cel has been on since the first time it stalled out.

Its a 2000 2.5L with about 60,000 mi. btw

what do you guys think?

Have the IAC checked.... sometimes they manage to gum themselves up. The check engine light can come on if the ECU detects a non-normal idle for a period of time.

Welcoem Saeros. Thanks for chiming in to helo a fellow CEGer.

Clean the IAC valve, MAF sensor, pour in a bottle of HEET/gas stabilizer in the gas tank and change the fuel filter.

Fuel filter.
http://www.contour.org/ubbthreads/showflat.php?Cat=&Board=v6maint&Number=958655&page=0&view=collapsed&sb=5&o=186&fpart=1

MAF
http://www.contour.org/mods/mods.php?s=howto&displayid=36

IAC cleaning
from Ray's UIM/LIM how to in Duratec Maintenance how to.

"Replacing the IAC gasket:
(From IAC faq)
Over time, the IAC (Idle Air Control) valve becomes sticky due to buildup from the EGR and PCV systems. It can stick partially open such that idle quality is adversely affected, and engine RPM's will not drop below 1500. For a while, blipping the throttle will restore normal idle, but this only works for so long.

The fix is to remove the IAC valve by unbolting the two 8mm bolts that hold it on and disconnected the wiring plug. If you are careful enough, replacement of the gasket will not be necessary. The gasket costs less than US $1.00, so it is no tragedy if you destroy it. Once the valve is off, spray it out with some carb/intake cleaner and make sure any gunky residue is gone. Reattach, and you are done. It is a lot cheaper than a new IAC, which runs around US $70. Note: Ford claims the IAC cannot be cleaned, but this is not true in my experience." Ray.

4th picture for location of IAC valve.
http://www.contour.org/ubbthreads/showflat.php?Cat=&Board=v6maint&Number=931756&page=0&view=collapsed&sb=5&o=186&fpart=1

thanks guys! i'll try that out and see what happens

I checked out this thread because tonight I was addressing the same problem. '98 SE auto that idled low and a little rough and then stalled. It would restart and drive if you shifted it quickly and got going, but then stall again at idle. The problem seemed to coincide with the onset of colder weather here.

I was prepared to deal with the IAC, but was hesitant given the admonishment, in bold letters, printed in the Chilton's book I just got at the library. Solvents, it says, shouldn't be used to clean the valve. The contrary advice between here and the book gave me enough pause to try the simplest thing first -- the battery, which was original and would likely need to be replaced soon, even though it started the car fine and otherwise appeared to be fully functional.

Putting in a new battery did the trick. As per the owner's manual, when the battery is disconnected, the car "relearns" to idle. When it started with the new battery, it was immediately different, revving up instead of weakly chugging along and stalling, and then it settled into a nice idle of about 800 rpm. I'm about 9/10 sure the problem is solved. There was no stalling in a half hour of city driving and a stop for gas.

So, if that other stuff doesn't work, maybe try the battery. In changing the battery, I cleaned off a lot of corrosion/crust from the posts and wires, which may also had something to do with it.

Hope that is of some help; I'm not a seasoned mechanic, but just wanted to share my experience fixing my idling problem in case it offers one more thing to try you might not have considered.

Welcome ljsense. Thanks for posting.