Ford Focus 1.6 TDCi - Error code P1181 (Solution)

Hello everyone.

I'm having a problem with my Ford Focus 1.6 TDCI, manufactured in December 2007, with 90 horsepower.

'Even during the summer, I experienced significant jolting on the highway, sometimes at full speed and sometimes during acceleration. This didn't happen in city traffic, where everything was fine.' It wasn't just a slight twitch, but a really strong jerk.
'Over the past few days, it's been very cold, and the engine has been sputtering, even in city traffic. In addition, the engine stalls after a cold start. It usually takes three attempts to get it started.' Generally, these described symptoms are more common when the engine is cold.
Fuel filter, air filter was replaced 8,000 km ago.
I once scanned the car's computer and found the following error code: P1181.

Does anyone have any ideas about this?
I would really appreciate it if someone could give me some advice.
Thank you.

P1181 is a manufacturer-specific diagnostic trouble code, and for Ford (and many other manufacturers), it indicates a "fuel delivery malfunction."

Consequently, all engine components that are related to the fuel injection system must be inspected. As a first and simplest measure, I would check if the engine is receiving air-free fuel and if there are any leaks: Inspect the diesel filter and fuel lines.