CAAC 2.0 CRDI Injector Noise / Valve Rattle

Hello!

I've owned my Multivan Startline 2.0 TDI (CR) with 103 KW since November 2010. I bought it with 12 kilometers on the odometer, and now I've driven it to 6000 kilometers.

Since then, there have been no negative reports about the engine, until now.

The engine sounds like it has swallowed a bag of seashells. The valves are making an extremely loud ticking noise under load, like a gasoline engine struggling. This is especially noticeable when accelerating from low speeds. The engine is knocking like an old 180 diesel. A dull hissing sound can also be heard, as if the exhaust is leaking. The power output is normal, but it seems to be consuming about a liter more fuel.

Previous repairs:

New clutch.
New gearbox.
Four new injectors.
Software update MSG.

Next Wednesday, I have an appointment with the doctor, and it would be helpful if I could have some information beforehand.

Error memory is empty.

Greetings,

Peter.

Today I picked up my T5 from the mechanic. Unfortunately, they couldn't find anything wrong.

I still need to figure out how to deal with all of this.

Greetings,

Peter.

How does it sound? Should I upload a WAV file? Perhaps try holding the microphone close to the device/module.

Best regards, Rainer.

Mc_Givertechnik wrote:

Hello! Previous repairs: New clutch. New gearbox. Four new injectors. Software update MSG. Greetings, Peter

ZMS changed, possibly the cause of the error?

Hello!

Thank you for your input. I had my T5 checked by a mechanic, who listened to it and, of course, thinks "everything is okay."

Auch hat er mir was von " ....gelernte Werte für die Injektoren zurückgesetzt...." erzählt. WaWhat does he mean by that?
Since then, according to the MFA (manufacturer's fuel consumption data), I'm using about one liter less fuel, which is exactly the amount it used to consume before the injectors were replaced.

To elaborate on your suggestions:
The engine runs perfectly smoothly at idle, with no rattling or clanging noises.

It only rattles under load, and especially in the lower RPM range.

Meanwhile, I've listened to other T5s with the 2.0 CR engine as I've driven past, and I've been disappointed to find that many of them sound like that.

Now the question is, do many 2.0-liter engines have the same problem, or does the engine in the bus simply sound like that? Is there a lack of insulation in the T5 that is present in passenger cars?

Greetings,

Peter.

... or it vibrates slightly in the relevant speed range on the bus.

Another theory is that the engines might be designed more for torque, which could result in louder noises. The insulation might also be contributing to the problem.

My random thoughts on the matter:

- Is the pre-injection being omitted under load?
-- Should be common practice in CR.
-- I've mostly heard about this issue with the smaller 1.3 Fiat/Opel engines.

- Does the Startline have less insulation?

Both scenarios are quite plausible for me (it's a CR, it's the absolute base model) and would also produce/transmit the described noises.

EDIT: Would a weasel or similar animal be likely to chew on a blind plug located on a splash guard?
When I drove my G3 TDI for two weeks completely without the lower interior lining to allow it to dry, everything sounded very, very different.


m;

Hmm, there are many possibilities, but there's something that somewhat challenges the "nude start line" theory.

The new Startline is fully lined on the inside and seems to be more than adequately insulated. Furthermore, my T5 was already very quiet, comparable to a CR (presumably referring to a specific engine type). It's true that the CAAC (presumably referring to a specific engine or system) doesn't have balance shafts, which manifests as a subtle humming sound under load in certain RPM ranges.

Outwardly, my car was always quiet, purring like a kitten, completely devoid of emotion, and rather bland.

Now it sounds like a Nissan or Mitsubishi direct injection engine, and it misfires even at low loads.

The exchange resulted in a worsening of the engine noise. Also, the fuel consumption increased, but it has since returned to normal since my last visit to the workshop.

My T5 Startline, as an extra feature, has an acoustic package with improved insulation and thicker glazing.

Greetings,

Peter.

Mc_Givertechnik wrote:

Auch hat er mir was von " ....gelernte Werte für die Injektoren zurückgesetzt...." erzählt. WaWhat does he mean by that?

Hi,

You can actually only reset the FMA and NMK learning values.
Someone has probably described this before, but if the search doesn't turn up anything useful...
Let me tell you a little bit about that...

Besides that, I can only think of IMA and (for piezo elements...) ISA alignment.
since these two calibration values are only written to the MSG once per injector.
(usually at the end of the tape) and not continuously, I hope that...
the workshop after the injector replacement you mentioned, the new IMA/ISA.
wrote the code...


Greetings, PD90.

Hello PD90.

Thank you for the information. Since this is my first CR engine, I unfortunately haven't been able to gain much experience yet. I searched for IMA or ISA, but unfortunately, I haven't found anything or I simply searched incorrectly. Because I'm not sure if my local dealer considered these options, I would like to check them. Would you possibly have the time and inclination to help me with some information? What values need to be entered where, and where can I find the correct values?

Thank you and greetings.

Peter.

Edit: I've now found something using Mr. Google.
Injector Quantity Matching (IMA) and Injector Voltage Matching (ISA).

How do you perform it?

You can find the IMA/ISA codes on the injectors; these are alphanumeric codes.
(e.g., 88SZ3N7SA => I just read that from a 1600 bar MV injector.)
from which the MSG calculates the offsets for the respective injector relative to the "golden injector".
(= Zero Tolerance Injector) was determined.
Each manufacturer can operate within certain boundaries and pursue its own strategies, but usually...
Several checkpoints are implemented in these codes, such as LL (Lower Limit), Emission Point 1.2, PI (Process Indicator), and VL (Upper Limit).
With all of this, the injector manufacturer (Bosch) has the opportunity to...
to slightly widen the tolerance range and adjust the corresponding deviation.
to be able to intercept and bring it back to the desired state (the "golden" injector state).
Previously (e.g., CR Generation1 1350bar MV), classification was performed during the production process.
For example, the items were divided into three categories (something like: thick, medium, and thin), and anything that didn't fit within those categories was sent back for rework.
There were 3 injector configurations stored in the MSG, which could be selected via coding.
When dealing with Böcken, you need to make sure you're using the correct injector class for a given application.
You will receive a replacement part!

However, in your case, after replacing the injector, the IMA/ISA needs to be re-flashed into the MSG (Main System Module).
Normally, this is handled by the diagnostic tool. However, I honestly can't say whether it's possible with VCDS.
Using Diagran and the original VAG tester is definitely the most reliable way to do it!

FMA and NMK are adaptation values that the MSG automatically calculates.
You can delete them, but if you do a few things after replacing the injector,
The amount of kilometers you drive, and even including a few bursts of acceleration, can be learned relatively quickly.

Hi, PD90.

Thank you, PD90.

Thank you for the very informative information.

Now, the question arises: Can I at least check the ISA/IMA codes of my injectors in the MSG via VCDS? Where are these codes located, and are they also precisely assigned to the individual cylinders there?

Best regards and thank you.

Peter.

Hi,

Here's a completely different thought:
The car is driven quite infrequently. It has 6,000 kilometers (approximately 3,700 miles) in 8 months. Is a significant portion of that distance short trips?

My CBBB (2.0 CR 125 kW) also rattles occasionally, every few weeks, for a while, starting a few minutes after a cold start. It rattles noticeably under the slightest load, but otherwise runs completely normally. I've always attributed it to the start of a regeneration cycle, but the idle speed isn't usually increased, which I think argues against that. Also, @dieselmartin has reported similar issues on his 2.0 PPD. Perhaps it's a warm-up measure for the catalytic converter? Interestingly, it never happens when it's freezing, but rather on mild mornings around 20 degrees Celsius.

@PD90:
Are there "Class 2 uncontrolled combustion events"? Or what do you think it might be?

@Mc_Givertechnik:
However, once it's properly warmed up, it runs perfectly smoothly.
Is your T5 ever driven for longer distances? Does that change anything about the knocking sound?

LL Drehzahlanheben wird bei normaler Reg. NOT DONE.

Only in cases where the issue becomes "more serious" - I've only observed this a couple of times so far - is it escalated to different levels.

m;

dieselmartin wrote:

LL Drehzahlanheben wird bei normaler Reg. NOT DONE. Only in cases where the issue becomes "more serious" - I've only observed this a couple of times so far - is it escalated to different levels. m;

"Mine does it every 400 km. If I suspect it's starting, I briefly disengage the clutch - then the RPM immediately goes to 950."