No codes. Runs perfect in the first 30 seconds after being dead cold (left overnight). That tells me that a sensor is not behaving quite right since I think the ECU ignores all sensor input in the 1st 30 seconds. I'm thinking that it has good enough signals to make the ECU think it is working correct, but the bad sensor is screwing everything up. I have had 4 mechanics try to figure this out with no luck. Manifold catalytic converters changed, disconnect exhaust pipe prior to the converter underneath so I know back pressure is not an issue. Fuel filter changed twice, air filter changed. Changed the MAF sensor (twice) no change. Getting ready to change the fuel pressure sensor on the fuel rail. The injectors are clean. Fresh plugs and coils. Somebody swapped the ECU, but I've had it checked out and reprogrammed, no change. I plan on changing the MAP sensor next, then the fuel pump control module. There is an indication that someone did something around the fuel pump. So I might change the fuel pump or see if it is seated properly. I've seen a bit of evidence elsewhere on the internet that other people have had this problem, but I see no answers applied to fix my problem yet. It does get terrible fuel mileage when I try to go anywhere so I'm thinking it is running rich. I don't want to drive it since the weak acceleration makes it really unsafe. Any ideas?

 

I had a very similar issue with my car, and I managed to resolve it after quite a bit of troubleshooting. It's frustrating when you're dealing with a problem like this, but you seem to be on the right track with your diagnosis. Here's what I did to finally fix my similar issue.

The TPS can sometimes cause these symptoms, especially if it's malfunctioning intermittently. Try checking and possibly replacing it. The IACV regulates the idle speed of the engine. If it's faulty, it could cause rough idling or poor acceleration. Cleaning or replacing it may help. malfunctioning Positive Crankcase Ventilation (PCV) system can sometimes lead to poor performance and rich fuel mixture. Make sure it's functioning correctly.

In my case, the culprit turned out to be a combination of a failing TPS and a small vacuum leak. After addressing these issues, the car's performance and fuel economy improved significantly. Given that you've already checked and replaced some components, it might be a good idea to review these possibilities.

 

> frustrating

That is a huge yes here to say the least.

> TPS

I've carefully checked the function with a multi meter and it seems to be operating ok. My problem is not an intermittent problem and the TPS is consistent, so I suppose it could still be a problem by not having the exact range, but the specs and the range seem to be fine.

> IACV

Idle is not a problem at all, just acceleration. Since this appears to mostly have to do with idle, I'll put this down the list. Idle is not a problem.

> PCV

Doesn't seem to be related and is a real pain to get to, though it's a cheap part. I'll put this down the list.

> Vacuum leak

I had this in spades. The EGR gaskets were gone when I got the car. I did a smoke test on the vacuum lines and found that problem. I made my own gaskets and retested with smoke and found nothing else. Still have the acceleration problem, but some other stuff improved, like the brakes work much better. lol.

> FPR

I changed this part since it is easy to get to and cheap. No change.

> MAP

I tested this. Everything checked out.

I'm going to do a fuel pressure and flow test next. EGR and battery are the only 2 things left on my original list. I've either replaced or tested ICV, FPS, MAF, MAP.

2 of the mechanics have changed the fuel filter. I'm not sure they did it because of fuel pressure or fuel flow or just common symptom and easier and cheaper to replace than test. Neither made a difference.

I have a friend mechanic that has a fuel pressure gauge that I'm hope to get from him. Check the rail pressure. Hopefully that is low and is either low because of a filter or a weak fuel pump. Relocating the gauge should tell me. There is evidence that a previous owner did something with the fuel pump, and may have put in a weak (possibly salvage) fuel pump. So I'm hoping that is the answer, but unlike everything else on this internet thing, I will post an answer when I find it. I am going to be the one to find it since I have yet to find a mechanic that can/will find it.

 

Have seen blocked cats in these before.

 

That appeared to be the initial problem. Noise like a belt squeal. Changed the front cats. Didn't fix it.

 

If you think it's a sensor, then check all the sensors, like the o2.

Do your mechanics not have live data tools to monitor the symptoms as they happen? Maybe find a mechanic that knows what they're doing rather than just guessing, or hit up a Ford dealership or whoever specializes in these Ford Escapes.