[mattlmr]

Hi guys n girls, we have a 2013 1.0 fiesta ecoboost with 83k it is the 125hp version (titanium) it has a severe lack of power and also hesitation sometimes when accelerating.
The lack of power is so bad it will not pull over about 70mph and it takes ages to get there, almost as if the turbo is not working, Now here is where it gets interesting! bear with me!
I have read so many posts of various forums with people that had similar issues, here is what we have done and discovered so far but still have the lack of power and hesitation-
Replaced spark plugs and coil packs, found one spark plug insulator was severely cracked and initially thought that was our problem but sadly after new plus and coil packs still the same although we did get rid of the misfire.
Also changed rocker gasket as that was leaking and filling up the spark plug area with oil, it certainly looks like someone has been in there before us!
Replaced the tiny silicone/rubber diaphragm in the take off on the vacuum pump as they are prone to falling apart which ours was, sadly still no power and hesitation.
I have tested the cam driven vacuum pump with a hand held vacuum tester and that all seems fine as does the actuator and blow off valve.
Inspected the high pressure fuel pump and bucket and cam lobe, all seem fine with no wear.
we have no engine codes when this started (well actually we brought it like this so its always had the problem)
However we now have fault code P0420 catalyst system efficiency below threshold bank 1
So is it possible the cat is at fault and has been all along but only now threw up a code?
Would a bad cat or faulty 02 sensor cause sever loss of power plus hesitation?
Im guess its possible the original cracked insulator on the old spark plugs caused over fueling which may have contributed to the possible cat failed?

Anything else i can test?

Oh checked the live readings of the 02 sensor on bank one and i took a video which i have attached a link to here-

From what i read the 02 sensor voltage on sensor 2 should be stable ish around 0.6v but ours dropped down to 0.1 a few times while recording, however after holding the revs at 3k for a few moments it eventually became stable at 0.6v

Let me know your thoughts and if there is anything else i can do the test etc.. before spending money lol

 

[mattlmr]

Just an update four you, We did a exhaust pressure test and that was all fine the cat is fine, we replaced the post cat 02 sensor and still same problem (low power and hesitation)
I have inspected the turbo inlet fins and they are fine turbo spins freely.
Did a cylinder compression test that was fine
Did a full leak down test and that was fine, all three had a little loss that could be heard through the oil fill cap but it was on all three and very slight. No bubbling in the coolant during the test so I'm eliminating clacked head or head gasket for now.

So now I'm really stuck as still no fault codes and still the problem exists.
Was thinking next step would be to get a cheap boost gauge and actually check its making boost.
Then possibly try replacing the low pressure fuel pump as I've heard these can cause similar symptoms but not show a fault code.

If anyone wants to add suggestions or ideas feel free to comment and let me know as I'm really at a loss now!

The only other thing I'm not sure is normal is when the car is running its sounds very quite and normal but if i remove the oil fill cap there is a load tapping noise from the rocker cover does anyone else's ecoboost sound like this when they remove the oil cap?
Possibly a fecked tappet/follower/cam loab? would that cause the loss of power and hesitation? remember we are down about 50% on power.

 

[Erkdajerk]

It sounds like you're being extremely thorough and diligent while trying to avoid an expensive visit to the dealer. I can empathize, but I hope that you're not being penny-wise and pound-foolish. The only thing I can suggest is to get the official Ford troubleshooting chart for "lack of power" (if it exists) and follow it until you find the cause. Good luck.

 

[mattlmr]

Just another update for anyone reading this, got a boost gauge and tested boost. that is all fine 10psi and overboost to around 15psi as per normal.
Got a brand new ford intake fuel pump/sender unit which also has the "lifetime filter" in, fitted that and still the problem exists.
Still no fault codes still car have half the power it should with general hesitation. the hesitation seem to be mostly under load but can also occur off throttle and and almost anytime throughout the rev range.

Anyone got any suggestions?
Next step is to try a used high pressure fuel pump with new tappet, then possibly look at getting injectors cleaned.

Remember we have done compression tests and lek down tests and all within spec and we have boost. coil packs and plugs new and gapped correctly.

 

[PeteN95]

Mine is doing something similar, missing/power loss under load in 5th gear. Still seems to pull fine in lower gears. I did get a flashing (!) check engine light when it first did it on a big freeway hill, but it went away when it flattened out and runs fine. I checked for codes, but there are none stored?