Speed signal in PID controller: Why?

Dear community,

First of all, thank you for the tips regarding the jerking issue with the 1Z engine. I drive a Passat from 1994 with a 1Z engine and have been experiencing jerking problems in 4th and 5th gear, at 1800-2500 RPM, for about half a year. Yesterday, I removed the speed sensor bridge from the instrument cluster, and since then, the jerking has stopped. However, the engine doesn't pull as strongly, and the turbo boost is less noticeable. The top speed and fuel consumption should be normal.

Okay, here's my question: What do I need the speed signal for in the mass airflow controller? Shouldn't the fuel injection amount only depend on the engine speed and not on the vehicle speed? I believe the vehicle speed is more relevant for the mass airflow sensor.

According to your explanations, when I drive without the speed signal, some changes occur (e.g., power cut-off/torque limitation). Do the injection quantities also change, or is the less powerful acceleration of my car since disconnecting the speed sensor more likely due to the (suspected) missing signal for the mass airflow sensor (MAF)?

Is there a built-in emergency program in the engine control unit that activates when the speed sensor fails, or are you simply accepting a loss of comfort features?

I plan to clean the flow regulator sometime, but I'd like to know if there's a significant difference in operation with or without a speed controller.


Sure, here is the translation of the text from German to English:

'l.g. weku'

'Best regards, weku'

weku wrote:

.... What is the purpose of the speed signal in the mass flow controller? ...

What do you understand by "menngenregler"?
If you're thinking about working with a solenoid valve for fuel injection, I strongly advise you to get the Bosch book on DI (direct injection) systems and go through it page by page.
Between the quantity interlocking and the gas wind tightness signal, there are still a few other things...

Quote:

... Actually, the amount of fuel injected should only depend on the engine speed. ....

The amount of fuel injected in a TDI engine is not linearly dependent on the engine speed. The load condition is also taken into account, and unfortunately, this cannot be achieved without a speed signal.

AAAAAAAAAAAAAAHHHHHHHHHHHHHHHHHH

There is a new edition of the BOSCH book "Diesel Engine Management" available.



And I only recently bought the (then current) older model.

How often are new versions released (mine is from 2002, and the new one is from November 2004)?

Both cost 45 EUR.

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