Golf IV TDI: Accelerator Pedal Signal Lost?

Good morning,
I'm having the following problem: As soon as I start giving it gas, the engine initially responds, but then dies after a few seconds. I have to release the accelerator and press it again. This doesn't happen when accelerating halfway or fully.
Before I let my Volkswagen dealership talk me into buying something, I'd rather ask about it here first.

Best regards,
M. Drees

Dieselmike wrote:

As soon as I start giving it gas, the engine initially responds, but then dies after a few seconds.

I have to release the accelerator pedal and press it again. This doesn't happen with half or full throttle.
Does the problem }always }occur (when the engine is cold/warm, when stationary and while driving...), as soon as and for as long as the accelerator pedal is in a specific range?

If so, the accelerator pedal is likely faulty.
-> Read the error memory or check the history of the accelerator pedal position during acceleration using VAGCOM.

Hello Ulf,
Thank you very much for your reply.
'It seems to be better when it's cold. It usually happens when I give it gas again after shifting gears, and then the accelerator pedal suddenly stops working completely. The error codes in the diagnostic memory only show errors related to a missing airbag control unit.'
Is VAG-com the software used by dealerships? I have a Bosch diagnostic tool. Can VW read the throttle position data?

Mike D.
VW T3 TDI

Hi Mike,

Is this about a G4 or your T3?

If you own a VW T3, what engine do you have?

If you have a 028 TDI engine (1Z, AHU, AFN) or similar, and you're using the G4 gas potentiometer, then you can be sure that everything is wired correctly.

Otherwise, it could still be the (self-made, often makeshift) wiring between the gas potentiometer and the control unit!

If it's a genuine G4 unit: Reading the accelerator pedal position – I don't know which device can do that. However, the free version of VAGCOM definitely can.

Okay, please provide the German text you would like me to translate into English. I will only provide the translation.

Hello Martin,

I installed the AHF Golf 4 (year 1999) engine, including the wiring harness and dashboard. The problem only occurred occasionally when the mass airflow sensor was not present. Now that 'everything' is supposedly working correctly, it happens constantly.
'The wiring issue isn't entirely unlikely, but it can be ruled out because if there was a problem with the wiring, the accelerator pedal wouldn't work at all. I'm taking the car to VAG tomorrow; they can diagnose it. But now that I think about it, it could also be the pedal sensors.'

Best regards,
M. Drees

Hello Mike!

I'm experiencing the exact same problem with my Audi B4 TDI.

I hope it's just the accelerator pedal position sensor!

Could you please explain what exactly happened and what it cost you to fix it?

Best regards, Daniel.

Dieselmike wrote:

But it could also be the pedal switches, I just thought of that.

Then, as far as I know, the accelerator pedal will be completely ignored and the idle speed will be set to 1200 rpm so that you can limp to the next workshop.

Hello,
The failure of the accelerator pedal signal was caused by the following: The holders for my brake and clutch pedal switches had shifted, causing the clutch position sensor (KPS) to be activated only sporadically, and the brake position sensor (BPS) not at all. The Bosch diagnostic tool is now showing me an error in the memory: 'Undefined brake signal.' I have now properly positioned them, and everything is working again. They must be able to be fully depressed. In production cars, a spring is built in as a buffer to ensure that the switches are activated completely.
By the way, VW can read out the pedal position as a percentage.


Best regards, Mike.
Mike.

Quote:

Volkswagen can, incidentally, read out the pedal position as a percentage.

We also .

If you're already driving a car with such an awesome modification and working on it yourself, why not build an interface and get VAGCOM?

Then you would have seen the percentages increase yourself (and you can also test the switches ).

Okay, please provide the German text you would like me to translate into English. I will only provide the translation.

Okay, please explain to me how I can get my hands on a VAG-COM device and what kind of connection equipment I'll need for it.
Okay... can anyone tell me the best way to display boost pressure? What kind of gauges are suitable, where can I get them, what about pressure sensors, etc.?

Greetings, Mike.

Dieselmike wrote:

Now, please explain to me how I can get a VAG-Com and what kind of connection technology I need for it. Okay... can anyone tell me the best way to display boost pressure, i.e., what kind of gauges, where to get them, pressure sensors, etc.

First, read the technical articles (on both topics), then browse the forum using the search function, and if necessary, ask again .