23 minutes ago, Mirko29497 said:

Guys, I really don’t know. This morning, after yesterday’s test, the car was running fine. As soon as I got back home, I immediately checked the values on Forscan and they’re the same as the ones shown. Fed up with the situation, a few days ago I bought a brand-new original Ford MAF, which still hasn’t been shipped, but given the situation I’m about to cancel the order (I was hoping it was the problem, since the car was running fine without the MAF).

Do you have the opportunity to return it for a refund after opening?

As long as you make sure the area around the MAF is totally clean, you could probably fit it carefully without marking it, then do a short run to test. If the problem is still the same then return for a refund.

The frustrating thing here is that it could potentially just be the MAF...but we won't know for sure unless you try another one. I'm not sure we're really getting any further with the testing now.

I think I’ll keep it; it certainly won’t harm the engine, even if it might end up being money wasted. Stupidly, I asked to ChatGPT for help by explaining the problem (Don’t hate me, I just tried.). I ran a test (same route as yesterday) but improvised a mixed route. I saved the .csv file and had it analyzed. He also maintains that there’s something wrong with the MAF and, secondly, the EGR (only in the background), due to values that aren’t quite within spec.

His Answer:

The ECU does not correct the DSD if the MAF reads incorrectly.
It works like this:

• It calculates MAF_DSD (the theoretical air required)

• It reads the actual MAF

If MAF < DSD:

• it reduces fuel

• it may increase EGR

• it limits torque

It does NOT lower the DSD to “follow” the MAF.

So:

High DSD + low MAF = faulty MAF or missing air

—not the other way around.

It would be interesting to see what ChatGTP would say if someone asked it how much Boost Pressure you would need to cram over 200g/s of air into a 1.5l Engine at 3000rpm.

Incidentally I have edited a previous post of mine where I wrote 155 kPa instead of 255 kPa.

We can try it! 😂

Obviously I’m joking — I took advantage of the situation to see how far it could go with a hypothetical diagnosis. As for the rest, I’ve decided to keep the new MAF and I’ll keep you updated. Strangely enough, today the car seems to be running well (even though it doesn’t have the same initial punch as when I disconnect the sensor).

Hi guys,

The new MAF (Original Ford) is arrived. Down i can show a new graphics (it was a short test in the traffic/town with some acceleration).

With the new MAF I’ve noticed a slightly quicker response off the line and, most importantly, it seems to have fixed an issue I was having: the feeling of being held back when lifting off the throttle. Ever since I bought the Focus, I’d gotten used to it having almost no engine braking, and now it finally feels like it’s back to how I remember it. Other than that, what do you guys think?

57 minutes ago, Mirko29497 said:

what do you guys think?

As before, the MAF looks fine, the MAP looks a bit wavy, something that I have never seen before.

Hi guys,
I wanted to update you on my situation. Thinking the issue was solved, today I went on a trip of about 100 km out and 100 km back. I noticed that when there’s some load (there were two of us in the car), performance drops noticeably.

While driving with cruise control on (95 km/h in my case), I noticed that the instantaneous fuel consumption increases even though the road is flat. Turning off cruise control doesn’t really help: the car still struggles to maintain that speed, and when accelerating it does move, but I have to press the accelerator much harder to keep or gain speed.

It feels like the engine is lacking torque and power. Even from a standstill the car feels sluggish—I have to give it more throttle, whereas with the MAF disconnected the car would start moving just by slightly releasing the clutch.

Hi everyone! I wanted to update you that I’ve had some work done on the car, but it still hasn’t solved my problem: it has low torque/power at low RPM and when starting off.

I cleaned the EGR valve (I cleaned it again today after 1,000 km and it was full of soot once more), replaced the MAF with an original Ford one, and repaired a vacuum hose that connects the solenoid to the turbo actuator.

What else can I do?

Thanks!

If the EGR filled up with soot in just 1000km then there is a problem with combustion. Best case scenario is one or more worn injectors. Worst case scenario is reduced compression due to engine wear or bad valve timing.

Thanks, Toms.

I will check the injectors if possible. The other suspect that comes to mind is the turbo solenoid, because I notice that the situation gets worse as the car warms up; when it’s cold, it runs better.

In addition, I checked the actuator movement: when the engine is cold, it compresses gradually over a couple of seconds, whereas when I turn the engine off, it decompresses gradually but with some difficulty and in a sticky way.

Edited February 23Feb 23 by Mirko29497

Update: In the past few days I replaced the vacuum control electrovalve/solenoid for the actuator, and I thought I had solved the problem, but that wasn’t the case. Besides the frustration of breaking some of the vacuum hose ends, I managed to fix them by reconnecting the ends with small rubber hoses. I really don’t know what to do…

Today there were three of us in the car, and you have no idea how weak it felt when pulling away — I have to really press the accelerator. No DTCs stored in memory, nothing at all…

@TomsFocus @Tizer One question: Is it normal that when I press the accelerator all the way down, the MAP sensor immediately shows a fixed value of 255 kPa?

Thanks so much!

36 minutes ago, Mirko29497 said:

@TomsFocus @Tizer One question: Is it normal that when I press the accelerator all the way down, the MAP sensor immediately shows a fixed value of 255 kPa?

Thanks so much!

When driving or when stationary?

That's around 37psi, which seems very high boost for this engine even if for full load.

@TomsFocus When driving... In the image I’m showing you the moment (in 3th o 4th gear, i don't remember) when I press the accelerator all the way down: I reach a steady 255 kPa from 2600/2700 rpm up to 3680 rpm, and then I release the throttle.

7 minutes ago, Mirko29497 said:

@TomsFocus When driving... In the image I’m showing you the moment (in 3th o 4th gear, i don't remember) when I press the accelerator all the way down: I reach a steady 255 kPa from 2600/2700 rpm up to 3680 rpm, and then I release the throttle.

Ok, I'm fairly sure that's not right but if it's true then I'm surprised the turbo can handle it.

I wonder whether it's been remapped before you bought it?

1 minute ago, TomsFocus said:

Ok, sono abbastanza sicuro che non sia così, ma se fosse vero mi sorprenderebbe che il turbo riesca a gestirlo.

Mi chiedo se è stato rimappato prima che tu lo acquistassi?

I have never remapped the car, and it has always been serviced at Ford dealerships for its maintenance.

3 minutes ago, Mirko29497 said:

I have never remapped the car, and it has always been serviced at Ford dealerships for its maintenance.

Did you buy it brand new? If not a previous owner could have remapped it.

Anyway, I've just realised I confused myself above. I forgot to take away atmospheric pressure. Because this is from a MAP sensor and not from a boost gauge. Once we take 15psi away that makes it 22psi of boost, which does sound correct.

Hopefully Tizer will confirm if I've got that right.

2 minutes ago, TomsFocus said:

L'hai comprata nuova di zecca? Altrimenti un precedente proprietario avrebbe potuto rimapparla.

Comunque, mi sono appena reso conto di aver fatto confusione. Ho dimenticato di togliere la pressione atmosferica. Perché questa è data da un sensore MAP e non da un manometro. Togliendo 15 psi, la pressione di sovralimentazione è di 22 psi, il che sembra corretto.

Spero che Tizer mi confermi se ho ragione.

I have buy the car one year ago with 205000 km.

I was browsing through some topics looking for some help and I came across this thread about a user who had performance issues that were resolved by replacing the battery. Could that be my case as well?

→ Focus 2012 MK3 1.0 125 - loss of power + PCM faults

Because I’ve noticed that I sometimes have intermittent errors stored in memory where the voltage shows 12V but also 11.8V (I have test now with TEST MODE and the value is 11,9 V and the Start-Stop work well). I still have a DTC that I cleared some time ago and that hasn’t reappeared so far:

===BCMii DTC B1108:77-28===
Code: B1108 – Driver’s door central locking motor

Additional fault symptom (:77):

• Commanded position not reachable

Status (-28):

• DTC previously set – not present at the time of request

• Warning lamp illuminated for this DTC

Module: Body Control Module

Freeze Frame #1:

• EVENT_TIME: 344641771 s (Fri Feb 13 14:08:35 2026) – Event time

• TOTAL_DISTANCE: 243196 km – Total distance

• MODULE_VOLTAGE: 12.0 V – Control module voltage

• INCAR_TEMPERATURE: 70 °C – Interior temperature

• PWR_MODE_QF: Power Mode OK – Power mode quality factor

• PWR_MODE_KEY: Key Out – Ignition key status

===END BCMii DTC B1108:77-28===

Update: Hi guys, I’m writing after a long time to update you on a change. In a thread I had opened on the forum, again related to the loss of performance of my Focus, I replaced the hose from the turbo to the intercooler that I mentioned in that thread, with photos included. The strange thing I noticed was the considerable stiffness of the new hose compared to the old original one; in fact, I had a really hard time installing it, but the situation hasn’t changed much.

I don’t know if you can help me with a new detail, but when I ask for power (especially when starting off after a junction) I notice that the instantaneous consumption reaches 44 L/100 km, something I’ve never seen in all the time I’ve owned the car. Once again, I have no errors in the ECU and I’m driving the car by pressing the accelerator harder to make it move or to maintain a constant speed. When I use cruise control, if I deactivate it I feel something like a jolt and then a subsequent slowdown… I’m giving as many details as possible to figure out what could be the culprit. I was also thinking about the MAP sensor… could it give incorrect values even if it doesn’t generate any DTC?

Really appreciate your effort and enthusiasm to research and test. I am facing similar performance/acceleration issues despite my Focus is 60K miles on the clock and it's automatic.
Hope you figure it out very very soon~

1 hour ago, Simon EC said:

Really appreciate your effort and enthusiasm to research and test. I am facing similar performance/acceleration issues despite my Focus is 60K miles on the clock and it's automatic.
Hope you figure it out very very soon~

Hi, I'm still struggling with the problem. I just got home for another MAP cleaning, hoping to fix it given the unusual graph, but obviously nothing. I even replaced the turbo silencer, but still nothing. I checked with a mechanic to see if the car was braking, and it isn't. I don't know what else to do: I don't know if there's still a leak from a hose (I recently replaced the hose from the turbo to the intercooler) or a vacuum leak somewhere. Unfortunately, there are no warning lights or errors via Forscan. The thing I've noticed lately is that I'm rarely experiencing very slightly longer start-ups.

Hey guys, I'm still struggling to figure something out. This is a new test where I was in traffic and proceeding at a walking pace, except for a few bursts of acceleration and a clear straight line towards the end of the graph. What do you think? The MAP is very noisy and I wanted to monitor the "Voltage" of the PID MAP that Forscan was providing. Could it be a faulty MAP?

Hi everyone! How is everyone doing? Hope all is well.

I'm reopening this thread to give you an update after a few months. I've just been driving the car and living with the problem, since the mechanics insist the car runs fine and I don't want to look like an obsessive psycho.

After replacing the MAF sensor, MAP sensor, turbo solenoid valve, and an intercooler hose as part of my own troubleshooting experiments, the car runs just a tiny bit better in terms of fuel economy, but the performance is lacking. On top of that, I feel a "pulled back" sensation every time I let off the gas, and I have to press the pedal more than usual just to maintain a constant speed.

Today, after going out with my girlfriend, I had to ride the clutch to make it up a hill because the car kept wanting to stall in traffic. As soon as I got home—despite checking it multiple times over the last few days with no stored codes—this evening I finally pulled an error: P2000 - NOx Trap Efficiency Below Threshold (Bank 1).

Tomorrow I'll check if the relevant sensors are okay, but after 250,000 km, I don't know if the DPF has reached the end of the line (even though I've done my best to give it hard runs, trigger regenerations when prompted, and take long trips). I checked its saturation level and it showed 17%, but who knows how much soot is actually in there...

Another detail is a sort of fueling "correction": I often feel the car's rhythm change, and I notice the instantaneous fuel consumption constantly fluctuating between 0.3 and 0.7 L/100km (when it was healthy, it stayed flat at a solid 0.4 L/100km).

One last detail is a long crank/extended start—meaning the starter motor takes a few more turns than usual to fire up, especially when the engine is hot.

On a simplistic level I'd check the DPF pressure differential as, my understanding (likely wrong) is that ASH buildup will give a higher reading than normal towards the time when it needs to be removed and cleaned (not necessarily renewed!)
Your NOx code may relate to AdBlue which I know little about but crystallisation and hence blockage of the injector is common (additive needed once the issue is sorted?)
The symptom of extended crank may be a clue...to something and slipping the clutch implies a major loss of power?