CR Injector Conversion: Piezo to Magnet Explained

Hi.

I happened to come across the fact that magnetic injectors are being used again.
The reasoning seems to be something like, "We're saving money on production, and the clueless end consumer won't even notice," or, more accurately, "cheaper to manufacture" and "switching almost as quickly as piezo elements."

The magnetic fun is called "2.0 CR TDI Generation II", in contrast to the "Generation I" piezo injectors.

Does anyone know more about this?
- since when?
- Is that the main difference between the MKB CBxx and CFxx models?
- Are only the injectors different?
- Does anyone know any details about why the exchange was made?

I was wondering why BMP and BMR were used in the 3C engine for years, and now that CBAB and CBBB have appeared, suddenly CFFB and CFGB have emerged.

m,

Hello Martin,

The CFFB engine in the 2010s A3 (103kW CR TDI) has a Bosch injection system with solenoid injectors and an EDC17CP46 engine control unit.

In theory, the piezo injector should be able to react faster, and therefore model the injection process more accurately. At least, that was the case with the piezo injectors used in the previous generation of common rail systems.

SSP445 wrote:

The company Bosch has developed an injector valve with magnetic valve technology, which meets the requirements for high injection pressures and the ability for multiple injections per combustion cycle. Solenoid-controlled injection valves have the advantage of being easier to manufacture than injection valves with piezoelectric actuators.

That is to say, current solenoid injectors appear to be technologically just as good, but are simply cheaper to manufacture.

For the engines I am familiar with that use piezo injectors (CAYA, CAYB, CAYC 1.6l TDI), there also seem to be some minor issues with the long-term durability of the injectors.
Perhaps that's the reason for the shift.

Best regards, Rainer.

Is my assumption correct?

CBxx = Piezoelectric material.
CFxx = Magnet

Please provide the text you would like me to translate from German to English.

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It also seems there are some minor issues with the long-term durability of the injectors. Perhaps that is the reason for the shift.

It likely serves as a preventative measure to avoid eventually receiving the undesirable "yellow lemon" award from the ADAC.

Just a few years ago, when towing a VAG vehicle, only the rear tow hook was needed.
Unfortunately, nowadays it happens too often that the front [part/section/area] is...

It's definitely due to the price; they are significantly cheaper to produce, and their switching times are already quite comparable to those of piezo elements.

Piezo injectors, whether for diesel or gasoline engines, have many problems in manufacturing and long-term durability. Whether you look at VW, BMW, etc., you can find countless horror stories about various piezo injector engine models, with years of troubleshooting without a solution.
I'm glad I switched directly from an AFN to a CFFB.

Best regards.
Christian.

Magnet valve injectors can also switch relatively quickly when powered like piezo elements.
In the field of agricultural and construction machinery, there is a motor that, when used with solenoid injectors, requires a current to initiate the opening, a holding current to maintain the open position, and a current with a reversed polarity to close.

This engine performs two pre-injection cycles and one main injection cycle until it reaches its maximum speed.

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In the field of agricultural and construction machinery

.

Should I save up for a Xerion after all?

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Should I save up for a Xerion after all

?

He doesn't have it. It's better to buy a Puma instead.

The "Generation II" 2.0 TDI engine has solenoid valves that are faster than the piezo injectors used previously. And, surprisingly, they are also cheaper.

Volkswagen doesn't have long-term problems with the 1.6 TDI engine, but rather manufacturing issues (due to the deliberately low price point). This results in issues like engine misfires and "incorrect" injector quantity adjustments. VW has spent a long time tweaking the software and often replaced injectors (especially in the beginning).

Hi Blackfrosch,

Delphi manufactures CR (Common Rail) injectors, which are controlled by a solenoid and a switching valve. A vacuum is present in the fuel return line, connecting the injector to the high-pressure pump. This vacuum is generated by a Venturi nozzle in the high-pressure pump. The vacuum, in conjunction with the switching valve, ensures faster movement of the solenoid valve.

Blackfrosch wrote:

The "Generation II" 2.0 TDI engine has solenoid valves that are faster than the piezo valves used previously.

You know more than VW does.

"... switching times that are nearly as fast as those achieved with a piezo actuator can be achieved with a solenoid valve."

m;

Almost, it can mean a deviation both upwards and downwards .

Hi Matthias,

Yes, that clever point also occurred to me, but:
If magnets used to be slower, then this one definitely isn't.

Because it's about getting closer.
Since the origin (we are talking about slow magnets) is clear, "almost the same speed" can only mean "but still a little slower."

That's how I would view it from a scientific perspective.

m;

You might be right. I'm glad I don't work in the automotive industry, where engineers are often outmaneuvered by salespeople. Here, I can still explore my ideas ...still...

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where the engineer is outmaneuvered by the businessman

That's exactly it.
It's no longer about "engineering" in the traditional sense, but only about ROI, marketing, and, above all, a detached and unrealistic legal system.

m;