Golf III TDI '96: Engine Stalling While Driving

Hello,

There have been similar posts here before; the mechanics I consulted couldn't really provide a helpful solution.

'During the warm-up phase, it sometimes stalls while driving. When it's warm (90°C), there's no problem. When it's completely cold, there's also no problem. The problem usually occurs when you drive a few kilometers, let it sit for 1-2 hours, and then restart it. This can happen 2-3 times in a row, but after that, everything is usually okay. Another noticeable issue is incorrect shifting behavior, for example, shifting from 4th to 3rd gear too early. Additionally, there have been instances where, after turning it off and restarting, it didn't shift properly (e.g., it stayed in 2nd gear). Only after stopping again, waiting a few minutes, and restarting did it run normally. During the described problem phase, it's also noticeable that the throttle doesn't respond correctly, or that the acceleration is delayed.'

I will soon check the relays; however, could there be other causes? I would be very grateful for any tips!

Hello,

Does the engine stalling only occur when braking (like downshifting a manual car without using the clutch and stalling the engine)? Or does it also happen when accelerating?

Do you have access to VAG-COM or a similar tool to check the error memory and other diagnostics? What has already been checked by the mechanics?

Regards,
Private.

It only happens when I release the gas pedal. It hasn't happened while I'm accelerating. Most often, it occurs when I'm stopped at a traffic light, but it has also happened on the highway at 120 km/h.

Okay, so far only the error memory has been checked, and it shows NO errors!

I checked the 109 relay, and it seems to be okay. Following the advice of a mechanic, I'm using the second key. Apparently, there might be issues with the transponder in the key used for the WFS (presumably a specific system).

I've done several test drives, and so far, the engine hasn't stopped running .

Well, is it really the key that's the problem, or is it a contact issue at the fuse box, relay, or something similar?

I will continue testing...

Okay, I don't want to spread any half-truths, but it probably won't be related to the key, since the code is only checked when the car is started, not during the drive... that doesn't really make sense...

rasputin wrote:

I checked the 109 relay, and it seems to be okay. . . . I will continue testing...

Hi,

Looking at it is not a reliable way to diagnose problems with the 109 .

If you suspect a problem, clean the contact points (by inserting a strip of paper between the contacts, pressing the contact down, and pulling the paper out) and, in the case of a circuit board version, re-solder all the connections.

Or simply replace it with a new part.

P.S.: The 109 is generally always suspicious :wink:in cases of stalls or engine failures during operation}.

but it probably won't be the key.

You're right, I also think that the thing about the key doesn't make sense...

Furthermore, I'm still wondering why he hasn't had any more issues with stalling recently, despite several tests (before I removed the 109, he stalled six times out of three trips). As I said, if it happens again soon, I will definitely take a closer look at the 109 (when I'm in my father's garage and workshop again...).

Here's another funny detail: the spring on the relay switch wasn't properly secured on one side, meaning the loop wasn't in the intended recess but was pushed further back??? => higher spring tension! Is this a production error??? It can't be that something like this shifts due to vibration. Nevertheless, it's questionable whether this ultimately has anything to do with the actual problem of the device turning off...

Thanks again for your comments!

I experienced another issue about 4 weeks ago; I was then able to obtain a soldering iron and resoldered the 109 and cleaned the contacts with paper. Since then, I haven't had any more problems . Thanks again for the tips!