dpf filter failing again after 2000km

[ramonskie]

a quick history.
i had a problem where 1 injector was malfunctioning and noticed this to late.
and this burned a valve in cylinder 3.
the injector was replaced and the valve/head had a revision.

we still had some black smoke coming out the exhaust when throttling the gas at idle.
then we wen trough a whole investigation phase we had all injectors tested
and found that 1 injector was a bit outside of the ideal values so we replaced that one.

and we also later found out that the dpf filter was broken.
i had the dpf filter revision. where they replaced only the honeycomb filter.
and the problem seemed to have been solved.
no more smoke and the values of the dpf tests where all good.

now i had driven 3000km with it. and when we did a dpf test again it failed for the APK (in the netherlands)
and now i also noticed that the black smoke is coming out again and its basically the same issue as before.

the car it self drives fine. and i do not notice any weird things like that it holding back. or when AC is on and underload etc.


i just checked with forscan the cylinder balance pids and noticed this
cylinder 1 between 0.105 en -0.005
cylinder 2 between 0.285 en 0.115
cylinder 3 between 0.115 en -0.010
cylinder 4 between -0.150 en -0.375

chatgpt says cilinder 2 and 4 are malfunctioning.
what do you think?
should i let the injectors get tested again?
or should i look somewhere else?

[metalworker0]

Assuming its a 2.0 ecoblue ... you must put this in your post .. because there are two engines 2.2 and 2.0 ecoblue answers will be different for each engine.

There's some basic things that can make it overfuel that should be looked at first

1. EGR faulty and staying open - you can monitor this in real time with forscan
2. Leak in boost pipes
3. MAF sensor faulty... note the maf sensor can shout fault if the above 1 and 2 are at fault.

Dpf also depends on vaporiser working as it should IN THE 2.2

Another thing that can block the DPF is a turbo on its way out .. leaking oil past the seals


GLOWPLUGS ON ECOBLUE
The next bit i got google AI to compose .. as it looked right .. i copied and pasted it as it saves a lot of typing

During a DPF (Diesel Particulate Filter) regeneration on a Ford 2.0 EcoBlue engine, the glow plugs continuously energize to support the combustion cycle. They provide the high cylinder temperatures needed to ignite extra fuel injected into the engine, which forces the exhaust and DPF temperatures up to the \(600^{\circ}\text{C}\) to \(650^{\circ}\text{C}\) required to burn off accumulated soot.Critical Role of Glow Plugs During RegenIgnition Assistance: The Engine Control Unit (ECU) triggers post-combustion fuel injection. The glow plugs help reliably ignite this extra fuel in the cylinder without causing harsh, premature detonation.Thermal Management: They maintain the minimum necessary heat in the combustion chambers so the regeneration strategy operates smoothly while you are driving.
Why Fully Functional Plugs Matter Regeneration
Inhibit: If a single glow plug is dead, or if the glow plug module registers a fault, the ECU may completely inhibit the regeneration cycle to protect the engine and emissions system.
Filter Blockage: Without active regeneration, your DPF will quickly clog, leading to a significant loss of power, reduced fuel economy, and potentially limp mode.
Oil Dilution Risk: If a regen is failing or struggling due to faulty glow plugs, the un-ignited diesel can bypass your pistons and dilute your engine oil.

those quantities of fuel .. sorry don't know .. all i know is in real time with forscan there will be commanded pid and actual pid .. maybe look at these . and if anythings out like the egr etc .. they will be wrong.

aln the best.mark

[ramonskie]

the egr is working fine the position and desired position are almost identical with 1.2% windows when accelerating. which seems more than okay.
also we cleaned the egr just to be safe.

so the only question is here are the values i posted for the cylinder any good?

[metalworker0]

Like i said i know nothing about Cylinder balance

Others here also .. a bit of a mystery .. you'd have to be at it every day .. your job as a diagnostic tech to look deep into them .

Many here use a "leak off test" to determine if an injector is at fault the leak off test is the way to go.

https://www.youtube.com/watch?v=t_ujxNjWBbM


Back onto cylinder balance.

Because i know so little - Here's what AI says about cylinder balance .

Cylinder balance PIDs (Parameter IDs) measure the power contribution of each engine cylinder. The Engine Control Unit (ECU) monitors tiny changes in crankshaft speed to determine if each cylinder is firing evenly. If a cylinder is underperforming, the ECU compensates by adding or removing fuel.

For a visual breakdown of how a car's computer watches the rhythm of the engine and flags uneven cylinder performance:
Cylinder to Cylinder Power Imbalance ·
Viewing live data on an OBD2 scanner, you will generally see numbers associated with fuel contribution, RPM, or torque.

The Baseline:
All cylinders should be close to 0 (or a neutral baseline like 90). Ideally, no single cylinder should be drastically different from the others.
Positive Numbers (+): If you see a positive number, it means the ECU is adding fuel or adjusting timing to force an underperforming cylinder to pull its weight.
Negative Numbers (-): If you see a negative number, the ECU is pulling fuel to calm down a cylinder that is working too hard.

What the Numbers Mean (Troubleshooting)
If one or two cylinders have high positive or negative values while the others are perfectly balanced, it is pointing you directly to one of three common issues:

1. Poor Fuel Delivery
The Data: A high positive value (e.g., +4.0 mg/str) or negative value (e.g., -3.0 mg/str).The Problem: A clogged, stuck, or leaking fuel injector is either starving or flooding the cylinder.

2. Weak or Failing Ignition The Data: ignore this one
High positive balance, often accompanied by a misfire code.The Problem: A bad spark plug, failing ignition coil, or faulty plug wire is preventing the fuel from burning efficiently

.3. Low Mechanical Compression The Data:
Consistently high positive balance on a single cylinder.The Problem: Burnt/leaking valves or worn piston rings mean the cylinder cannot hold pressure, resulting in a severe drop in power.

all the best.mark

[metalworker0]

cylinder balance .. question into google

Diesel, what is considered very high and very low in a cylinder balance test?


In a diesel engine, a cylinder balance test (often called an injector balance rate test) tracks the fuel compensation needed to keep a smooth idle. "Very low" or negative numbers indicate the cylinder is producing too much power (over-fueling), while "very high" positive numbers mean it is under-performing and requires extra fuel.
Normal vs. Extreme Ranges (Measured in mm³ per stroke)
While ideal limits vary by manufacturer and engine type, general guidelines for a fully warmed-up engine at idle include:
Excellent/Normal: Between -2.0 and +2.0 (depending on your model, this is the expected factory sweet spot).Acceptable/Tolerable: Usually up to ± 3.0 or ± 4.0.Very Low (Over-fueling): Anything below -3.0 or -4.0.
A negative rate means the engine's computer is taking fuel away from that cylinder because it's running too strong or the injector is leaking/worn.Very High (Under-fueling): Anything above +3.0 or +4.0.
A positive rate means the computer is adding fuel because the cylinder is weak and needs help to fire evenly with the others.

Absolute Limits:
Readings exceeding ± 15.0 are considered the absolute maximum limits and often immediately trigger fault codes or "limp mode".
What the Extremes Mean
Balance rates highlight relative performance, not just the health of the fuel injector. If you see extreme numbers, the culprits generally include:
High Positive Rates (+): Often caused by a clogged or restricted injector, low compression (due to worn rings or a bad valve), or low fuel pressure.
Low/Negative Rates (-): Typically caused by a physically worn, stuck-open, or over-delivering injector that is dumping too much fuel into the cylinder.

Because these tests only measure a vehicle’s cylinder contribution at idle, they are best paired with manual diagnostics. - injector leak off test

I could be wrong ! So going by that, yours are all within the normal range -2 to +2.. only differing by tenths rather than whole numbers .. well that's my interpretation of it. no extremes.

now if a leak down test proved otherwise, .. then it makes the cylinder balance test a non item

all the best.mark

[ramonskie]

yes i also found this information.

but the problem is that most information is for older engine type and not for the ridiculous over engineerd eco blue systems
which have lower tolerances i think.

so maby its best at this point to just go to a engineer at a ford dealer and ask them what the tolerances are.

[metalworker0]

there are ford engineers here member "FRAG"

I don't know if the tolerances are like you said

so you are saying: the "tenths" do matter

i don't know?

I say get into it , get the leak off test equipment .. its cheep .. ford now charging £100 plus vat an hour for diagnosing .

https://www.ebay.co.uk/itm/366454766242?

its up to you ..i dont know what your age is, or your abilities

but looks simple enough to use

my enquiries on the net seem to indicate: Generally, any reading outside of ± 3.0 mm³ per stroke..

There are others that will hopefully contribute, otherwise its me learning as i go, i myself have a tddi connect.. which isn't the same set-up .. so i don't have practice experience ..

all the best.mark

[metalworker0]

I asked the question .. for euro 6 . (2015 onwards). and it was the same answer

all the best.mark