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2006 Escape 3.0 - low idle when cold

Hello, all!

I found several FTE sites on the Interweb, and apparently I am already a member of at least one of them, even though they can't confirm my email. Oh, well...
So, now i"ll jump right into the problem...:)

About 2 years ago, right after I had my spark plugs changed at 100K miles (and intake taken off), I noticed that, in cold weather, when I came up to the stop sign at the end of my street, the engine idles down to about 400rpm and feels rough. By rough, I don't mean uneven, as I can't hear or feel a miss. After the car warms up, it gradually does better.

I have had the IAC valve, EGR valve, DPFE sensor and intake gaskets replaced, had a fuel system cleaning, and the dealership performed a computer upgrade, fuel trim adjustment and vacuum test. The problem is that by the time the mechanic gets the car, the engine and engine compartment has warmed up and the symptoms disappear.

I suspected the intake gaskets, that there was a 'cold leak', and as the engine warms up, the gasket material gradually expanded and sealed the leak.
It does seem to run better since the gaskets were replaced, but I don't think it's completely fixed. I will know when colder weather rolls back around.

The only thing left to look at, as far as my limited knowledge is concerned, is to more closely investigate the vacuum lines (since they are now 9 years old), and maybe have the dealership go into the computer and raise the curb idle. I may also look into changing out the PCV valve, as that essentially has to be removed just to change the air filter.

Has anyone else experienced this? Any advice?
Thanks!
 

blacksnapon

Moderator
Staff member
Use carb spray with the nozzle to precisely direct the spray. When its running (cold I assume) spray intake gaskets, grommets, hoses, p/b booster. When you spray the leak, the engine sound will change. Some people will use a propane cylinder with a tube attached.
 
Thanks!
Intake gaskets are new - less than a month old.

How would the brake booster affect it? Would it be worse when cold and better when warm?
I have noticed that the rubber boot around the booster makes an annoying noise, like it's all dried out. I have sprayed it with silicone.
 

fatherdoug

Tonto Papadapolous
The line that goes into the rubber boot on the side of the booster is a vacuum line. Sounds like the boot needs to be replaced?
 

dustybumpers

don't play well w others
Check TSB's.
My brother's Escape, as well as his daughter's required a throttle body change at around 60,000 miles.
Symptoms were similar to yours
 
Thanks, y'all!
Dustybumpers, pardon my ignorance, but what is a TSB?
My mechanic 'cleaned' the throttle body when they did the fuel system cleaning.
I am somewhat of a 'novice' about this stuff.
I have noticed that my brakes feel kinda 'spongy', and the pedal makes a mteal-against-rubber noise when the mechanism hits the boot. I have sprayed the boot with silicon.
I asked my mechanic if there is a tie-in between the brake issue and the idle issue, which to me, with my limited knowledge, seems like some 'outside air' is getting into the combustion chamber, and/or the system is not 100% airtight.
The brakes on my 2000 Explorer feel a LOT better...
 
My mechanic kept the car for two days, he can't find anything.
He did the carb spray test, he even tested for a leaky head gasket.
I assume he checked all vacuum lines, including brake booster line.
Nothing.
He gave it back to me and told me to bring it back if it acted up again in colder weather...:headbang:
 
This car is still driving me nuts....

Recently has the valve cover gaskets replaced, still no change.
A while back, the CEL came on, O'Reilly's checked it out, it pointed to an O2 sensor. He cleared it, and the CEL has not come back on.
What symptoms would a bad O2 sensor produce?


There are a few things I'm wondering about;

1) PCV valve and hose. To my knowledge, these have never been replaced, and the car is ten years old. What would my symptoms be if it was this?

2) Could I have a hairline crack in my intake manifold?

3) My mechanic replaced the power steering pump hose with a hose from a rubber company, so it's not an actual Ford replacement part. Could this be affecting my vacuum?

4) My a/c has a leak somewhere. I have to put a can of 134 in it about 2-3 times a year. After the last recharge, I heard a hissing noise for about ten seconds after turning off the engine and disconnecting the the connection. Could an a/c system leak cause a vacuum or idle issue?

I have asked my mechanic about the possibility of a bad vacuum line, but he said he didn't find one.

Whatever this issue is, it is affected by cold weather. That tells me that outside air is getting into the system somewhere. I even hear a rattle/gurgle/whoosh sound when accelerating from a dead stop.
As the car warms up, it runs better. It is almost hard to start on really cold mornings. When I come to a stop, the rpms go down to about 500 and the whole car vibrates. There isn't any kind of rhythmic miss, so I don't think it's a spark plug or wire.
 
Injectors cleaned
Throttle body cleaned
EGR valve replaced
DPFE sensor replaced
IAC valve replaced
Upper and lower intake gaskets replaced
Valve cover gaskets replaced


Guy at Ford dealership suggested that it might be the fuel pump...?

Outside air is affecting it. When it gets cold outside, it starts to run rough, and it's using more gas.

What would symptoms of a bad PCV valve & hose be?
What would symptoms of a bad O2 sensor be?
 

SuperCab

Moderator
Staff member
10,068
547
Montana
They should be able to test the fuel pump pretty easily. Put a pressure gauge on it and see if it's pumping up to spec or not.

Don't know what the symptoms of a bad pcv valve would be aside from some moisture buildup in the crankcase... Don't imagine it would cause drivability issues but I don't know for sure.

O2 sensor shouldn't affect cold start idle I don't think. Could contribute to your fuel consumption issue though. But the colder weather can be enough to so that on its own.
 
They replaced a bad motor mount, PCV valve, and 'cleaned' the MAF.
It is smoother, but the idle still drops to 500 on my onboard tach at stoplights.
I shift into neutral, and idle goes up to about 650.
Should there be that much difference in RPMs between D and N?
I wonder if they can just go in the computer and raise the curb idle....
 

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