Ich weiß nicht mehr weiter, Hilfe mein TDI spinnt !!! | Posts 16+

Hi Ulf!

I used a diesel return hose from the injectors as a suction hose. Of course, it's difficult to connect it to the valve... However, the cross-sectional area is much smaller than the standard hose for the valve. The pressure is P = F/A, meaning that with a smaller cross-section, the required force is also smaller for a constant pressure, or am I mistaken?

Best regards, Christian.

Hi,

haehnlein wrote:

...The cross-sectional area is much smaller than that of the standard hose for the valve. The pressure is now F divided by A, which means that with the smaller cross-section, the required force on it is also smaller for a constant pressure, or am I mistaken???

No force is acting on the hose's cross-section, but rather on the surface area of the rubber membrane inside the container. This membrane moves against the spring force of the valve.
Therefore, it doesn't matter what kind of hose you attach.
You are right, the concealed compartment is difficult to draw from (it only works with mouth suction, otherwise it will pull air into your lungs through your throat ). It's better, as Ulf already said, to use a large syringe or a bicycle pump with a reversed piston.

Best regards, Rainer.

Rainer K. wrote:

No force is exerted on the hose's cross-section, but rather on the surface area of the rubber membrane inside the container. This membrane moves against the spring force of the valve. Therefore, it doesn't matter what kind of hose you attach.

Hi Rainer!

I need some force to push the air molecules out of the system, and that force should decrease with a smaller "suction area" at a constant pressure, right? It's basically like a hydraulic press, or not? Well... but the vacuum in the jaws must correspond to the pressure of the system -> so maybe it doesn't really matter what hose size. The syringe is of course better... but I didn't have any problems with the hose at all .

Best regards, Christian.

@Ulf
Regarding "hissing noises." Does this necessarily indicate a leak on the pressurized side, or could the noise also be caused by a leaking vacuum hose for the turbocharger pressure regulation? I've been experiencing exactly this symptom in my AMF for some time now. The amount of soot is no more than usual (it produces a bit of soot anyway due to the chip under full load), and in fact, it might even be slightly less.

Regards,

Olaf.

Olaf wrote:

Regarding the topic of "hissing noises". Does this necessarily indicate a leak on the pressurized side, or could the noise also be caused by a leaking vacuum hose for the turbocharger pressure regulation? I have been experiencing exactly the described symptom in my AMF for some time now. However, the soot production is not more than usual (it produces a little soot anyway due to the chip under full load), and in fact, it might be slightly less.

Hi.

Hissing sounds from charging cable leaks are usually also audible while driving (the louder the sound or hiss, the more the accelerator pedal is pressed ).

Due to their extremely small size, leaks in fuel lines are likely to be audible only as a faint hissing sound when the engine is running, and only if you are very close to them.

Hi everyone,
"I finally got around to doing what you suggested. So, I deactivated the AGR valve. The performance has improved significantly, but it's still not optimal! Could it be that I need to "break in" my engine again? After all, I've been driving with a faulty AGR valve for at least 20,000 kilometers."
Now that it's gotten so incredibly cold, I'm having significant problems starting the car. I suspect it's the glow plugs. Blue smoke and a long cranking time are the symptoms. Could the slight loss of power also be due to faulty injectors? The engine also sounds very rough.

Regards,
Reuselkopp.

reuselkopp wrote:

So, I deactivated the AGR valve. The performance has improved significantly, but it's still not optimal! Could it be that I need to "break in" my 1Z engine again? After all, I've been driving with a faulty AGR valve for at least 20,000 km.

Hi.

How did you suddenly know that the AGR (Abgasrückführung) was defective? Was it not opening or not closing properly?
In the latter case, the intake manifold might be so clogged with soot that the engine struggles to breathe. Have you ever looked inside the manifold?

Quote:

Now that it has gotten so extremely cold, I am also having significant problems starting the car. I suspect it is due to the glow plugs. Blue smoke and prolonged cranking are the symptoms. Could the slight loss of power also be due to possibly defective injectors? The engine also sounds very rough.

Rough sound can be caused by an incorrectly adjusted pump. Worn nozzles are also a possible cause, as far as I know.

Hi Reusel,

My TDI has a similar mileage to yours. Last month, it got new injectors, and they've already made a difference.
Less soot, smoother operation...

Since the temperature has dropped below freezing, I've noticed that my glow plugs aren't working as well as they used to. It now takes a long time for the engine to warm up, and there's some rattling. This wasn't the case last winter.

I think that at 136,000 km (approximately 85,000 miles), it's quite possible that components like spark plugs would need to be replaced. It wouldn't be unusual.

Unlike the nozzles, candles don't exactly cost a fortune either .

Greetings.
Thomas.

Hi Ulf,
I once received an email from Rudi describing how to disable the AGR (Abgasrückführung). Instead of the gasket between the AGR valve and the intake manifold, I installed a copper sheet that was cut the same shape as the gasket, but without the hole. Now the engine runs better. So, the AGR was the problem, right? The closing mechanism was also very clogged.

Regards,
Reuselkopp.

Hi,
Okay, one more thing. I haven't looked inside the exhaust manifold yet. How thick can the soot layer be? What's considered normal?
The start-up process was recently checked and was completely fine, according to the VAG workshop.

Reuselkopp.

reuselkopp wrote:

Hi, Okay, one more thing. I haven't looked inside the manifold yet, how thick can the soot layer be, what is normal?

Hi.

I would say that 2-3 mm is still acceptable, but beyond that, it might start to become a problem, especially in the thinner individual tubes after the 1 in 4 transition.

Merry Christmas from Diesel!

Okay, now let's get to my problem!
The well-known problem with the TDI engine is occurring again. I've been to Bosch several times, supposedly specialists in this area, and also to a VAG dealership.
'I've been to several workshops, but no one can really help me. They just want to replace everything possible without testing anything, just based on a gut feeling.'
Okay, so the symptoms: loss of power! This manifests as poor throttle response, lack of flexibility in the higher gears. For example, I'm driving at 120 km/h in fifth gear and want to accelerate quickly to 150 km/h, but it doesn't respond at first; it takes a long time before it shifts, and while it's trying to accelerate, the engine sounds strange, almost like it wants to but can't. In the lower gears, it drives almost normally, but you always feel like it's missing the right amount of power. I bought the car, a 1995 Golf TDI with 90 horsepower, six months ago. After the purchase, it was discovered that the turbocharger control valve was defective.

I don't think the injectors are broken; they're probably still new after so few kilometers (mine have 230,000 kilometers and still seem to be working)!
'To me, it sounds like the engine control unit (ECU) is switching to emergency mode. I experienced this under heavy load (going uphill), but not necessarily at full throttle, at a similar speed (110 km/h). The power loss was sudden, but of course, it was while going uphill! I had to shift back to 4th gear to maintain speed or accelerate slightly. The solution was that the turbo pressure sensor (in the ECU) was not providing an acceptable value that matched the load. A badger had caused this damage, almost invisibly. It had gnawed on the hose from the intake manifold (I'm not sure if that's the correct term for the TD, as there's sometimes overpressure in it) to the ECU. The bite was so small (as I said, almost invisible) that it only resulted in a loss of turbo pressure under very high load. A friend (also with a 1Z engine) had a problem with the ABR valve being leaky (it was clicking during the pressure test). In that case, disabling it wouldn't have helped.'

Now, I have another question: Where can I get the schematic for Ulf's selection electronics?
And does anyone know the problem where the idle speed is not kept constant, and under load in first gear, the car stalls (kangaroo jump )?

Wishing you successful tinkering!
punctuated

You can find diagnostic adapters for VW/Audi on the community forum. Then, click on 'revised standard circuit.' Use C-type transistors (BC547C) for the transistors.
Or here:
http://www.dieselschrauber.de/Adapter%20trimmbar.jpg

You can find diagnostic adapters for VW/Audi on the Community page. Then, click on the 'revised standard circuit.' Use C-type transistors (BC547C).
Or here:
http://www.dieselschrauber.de/Adapter%20trimmbar.jpg

Thank you very much!
Hopefully, I'll be able to convert this into a layout and etch it soon!
Do you have any experience with the adapter from Elektor?
I really need to delve into this more; a TDI engine is incredibly interesting, and the workshops don't even realize how great they are! If only I had more time!

Regards,
A

André.

apunkt wrote:

And does anyone know the problem where the idle speed is not kept constant, and under load in first gear, the car stalls (kangaroo jump )?

Hi.

"Jerky behavior typically manifests in higher load and speed ranges."

Even at idle, the usual suspects come to mind: the mass airflow sensor (MAF) and relay 109.
Furthermore, an adjusted or difficult-to-operate mass airflow sensor --> use VAGCOM to read the alleged idle air mass, and if necessary, correct it.

Hi.

'Jerky behavior typically manifests in higher load and speed ranges.'

Even at idle, the usual suspects come to mind: the mass airflow sensor (MAF) and relay 109.
Furthermore, an adjusted or difficult-to-operate mass airflow sensor --> use VAGCOM to read the alleged idle air mass, and if necessary, correct it.[/quote]

Hello,

Okay, I'll take a look. I recently had the control unit read out at a VAG workshop, and it was free! The ignition timing was fine. It just showed a sporadic error code 27 (I think), which indicates a missing speed signal.

Regards,

André.