Engine Shaking Cold: 1Z Engine Issues

Hello fellow diesel enthusiasts!

I'm having a problem with my Audi 80 1.9 TDI 1Z engine, manufactured in 1993.
Especially when I start driving in the morning, my TDI engine jerks, particularly if I don't press the accelerator pedal all the way down, meaning when I just want to maintain my speed at a low RPM.
When I'm fully accelerating, in boost mode, I think I can feel that it sometimes injects fuel in spurts.
When I press the pedal, it responds well and delivers its power.
The diagnostic device in the workshop reported an implausible signal from the needle lift actuator.
I already replaced it, but it hasn't made much of a difference.
After running about 20 km, it gets a little better, but it's still not running perfectly smoothly.
Can anyone give me some tips on this problem? Hopefully, it's not related to the ESP (Electronic Stability Program)!!

Best regards, Hans.

Hello,

An implausible signal can also be caused by a cable defect.
Was the error memory read out again after the replacement?

No, probably I should have it removed. I've tried measuring all the values described in the book "How to Help Yourself," and I haven't noticed any significant deviations.
If it were a cable problem, where are the most likely points of failure?
Another question: How does it manifest when the ESP is slowly failing?

Best regards, Hans.

Hello Hans!

I have the same engine. After a cold start (especially in winter), it's a bit jerky – I experience the same thing. The older 1Z engines still have the slow-responding turbocharger, which results in a less favorable torque curve up to about 2100 RPM. This makes low-speed driving a bit more difficult for us.

You can check the ESP (Electronic Stability Program) for leaks by inspecting the area around the pump and timing belt – unfortunately, this is the case for me (362,000 km).

If you can read the error codes, please post them again in the forum. Unfortunately, I haven't been able to do it yet, even with several adapters.

Hello,

I've managed to resolve the issue. I replaced the diesel filter, and the 1Z is running smoothly again.

Thank you to everyone who gave me personal advice, and also to everyone who participates in this forum.

What I learned from this: Don't immediately assume it's a major problem; first, try the simplest solutions, and then you can investigate further.

I've been troubleshooting the problem for weeks, even switched NHG providers, and I might regret that decision today.

Perhaps I can help others with my experiences. I will definitely stay active in this forum.

Best regards, Hans.