Engine Misfire at 20°C? Troubleshooting Guide.

My 1996 Audi A4 is experiencing that annoying idle fluctuation problem again!

I already went to the Bosch service, but they want to replace the entire pump right away. The local dealer is clueless again! That's why I'm turning to you guys once more!

'When the outside temperature is above 20 degrees Celsius, my engine vibrates at operating temperature when idling! This vibration is not visible on the tachometer; you can only feel it through the seat and by the erratic movement of the gear stick! In 40% of cases, the vibration disappears if you briefly accelerate.'
I'm also experiencing the same jerking when I'm rolling towards a traffic light in a higher gear, without shifting, and braking, especially when the temperature is above 20 degrees Celsius.

Since the problem only started after I installed the new cylinder head, I suspect there's an issue with the settings! But according to the Bosch technicians, all the values should be correct!

Do you know this problem, or what exactly is the Bosch technician supposed to be focusing on? Unfortunately, I still don't have a VAG-COM, but I'm going to buy a laptop now! It's cheaper in the long run!

I will have the Bosch representative bring this technical article. https://community.dieselschrauber.org/en/viewtopic.php?t=658

I hope that issue has been resolved. But why does the error only occur when the outside temperature reaches 20 degrees Celsius?


Okay, here's the translation:

Thank you.

Manuel.

When I read your signature, several suspects come to mind.

My ALH engine vibrates when the air conditioning is on and I turn adaptation channel 1 to its maximum value... just as an example.
Try turning it there...

CU Gremlin.

Hi,

Perhaps not helpful for the problem, but still relevant to the topic:

When my ASV was brand new, it also had the jerking issue, exactly as described, but only when it was cold.

It then disappeared suddenly (somewhere within the first 3000 km, I don't remember the exact mileage) and hasn't reappeared since (now at almost 40,000 km).

Best regards,

Jan.