I have a 05 Escape 4cyl, auto, 95,000. I bought it used at 28,000 mi. It runs fine when you start it, and it's cold. After you drive it for awile, and everything warms up, it tries to stall when you come to a stop sign. Half the time, it does stall. I have to put it in neutral, give it a little gas, then pop it into drive to get going. Then, it'll run fine until I stop again. Also, if I put it in park start it, it starts fine. Then switch to drive or reverse, it'll stall out. Only does any of this after the car is warmed up. I have replaced the spark plugs, fuel filter, and oil. It has a new air filter, and I also cleaned the Mass air flow sensor. Still doing it! To my knowlege, it has never had a transmission oil change. If I change it, I don't know if it would make a difference. Any ideas?

One thing to note...I have noticed in the last 6 months, a weird shudder in the engine/transmission when it auto shifts down a gear from overdrive.

Also...engine idle is fine. Purrs like a kitten when sitting. But struggles a bit when under a load(Put into drive or reverse)

Please help!!!!

 

Have you replaced the IAC valve?

 

No...should I? Would that be a good "Next step"? The check engine light isn't on either.

 

You should removed the IAC (idle air control valve) and see if you can see any carbon deposits. They are often a trouble spot on Fords and often you can clean them and put them back on. If this makes a noticeable improvement I would go ahead an put on a new one as they don't cost much.

 

I removed and cleand the IAC, and Throttle body. Got it back together...test drove it....and now it accelerates sluggish. If I gun it from a stop, it'll accelerate fast, but has a difficult time progressing to the next gear. While driving normally, if I give it gas to accelerate, it won't downshift....and accelerate. It's a gradual acceleration. I'm totally lost at this point. I didn't unhook the battery while I did everything (Probably should have) so I unhooked it last night so mabye the computer can reset. I'm going to hook it back up the morning and see how it does. It didn't stall at stops, but wanted to. It still stalled when I put it into drive from park after the car was warmed up though. Any more thoughts?

 

Disregard that last post. I forgot to plug in the Throttle Position sensor when I put everything back together. I'm such an idiot!!
It seems to have improved a bit, but is still wanting to cut out at stops. The rpms go wayyy down to the point were it wants to stall, but doesn't. Also, from park to drive, it still wants to stall...but now it's sporatic. Sometimes it does...sometimes it doesnt. At least it stays running now....for the time being. Could the IAC be it? Any other thoughts?

 

There is a way to test the TPS and the IAC, but you need a CHILTONS manual, and voltmeter to see if they are functioning correctly..The manual will walk you through the test procedure..

 

You might need more than a ordinary voltmeter since the IAC is a PWM operated. At least a DMM that reads duty cycle with the +/- slope option like a Fluke 88. Not sure if they ever fixed it but the OTC DAT wouldn't work on a Ford IAC because it didn't have the slope option. I still have their prototype with the slope option added. It was supposed to be added into production. Since that was years ago, I "assume" it was done!

 

thats what mine did before I changed the iacvalve .no cel on either did its range of idle then be fine and do it again 3 days later or weeks later.

 

The Chiltons basically tests resistance on the IAC, and tells you the parameters, and with the TPS, it gets a little more involved..I'm not that big into the electronics side, just offered what I read-did not say it was "RIGHT", but its the only info I had to offer...

 

I'm sure a basic resistance will tell you if it's open. A Ford manual will list duty cycle at idle, most often around 30%. Like I said it's PWM(pulse width modulated), so putting 12V on it does nothing at all. Even better to use a scope if you have one.

A TPS is actually easier, it's just a variable resistor. You can remove it, sweep it while checking resistance looking for flat spots. Running at idle should have around 1V output and be steady. You have to backprobe the connector. A paperclip can be used on some connectors but I'm not sure about the Escape connectors!

 

The IAC is pretty inexpensive and sometimes taking them off and cleaning them doesn't fully fix the problem. I'd be tempted to replace the IAC.

 

I'm no expert, but I think you're shooting the wrong trouble. If it idles OK in Park or Neutral, I'm going to guess that the IAC is OK. I think your torque converter is locking up, and not releasing when you slow down or stop.
You mentioned shifting troubles, try a tranny flush; soon! You don't want to spend $3,000 on tranny repairs. And look into torque converter problems.

 

Don't know it you have got it fixed, but a guy that I work with had to replace the torque converter in his mom's 04 with about the same amount of miles. There is a TSB out on this so you might look for that and see if you are having the same issues.

 

I had the same problem... I changed my plugs and it was fine after...
always remember K.I.S.S. (Keep It Simple ......)