What are some good maintenance for fuel improvement?

[3246cc]

Like oil, oilfilter and air filter.
But what can cause diesel bad fuel economy? Sensors? LMM? Etc

 

[supton]

Tire pressure, did you check that?

 

[3246cc]

Tire pressure, did you check that?

Yes, also! I did some engine diagnostics (reading with obd) no fault codes. I drive and don't pull hard, i drive on cruise control

 

[dnewton3]

You are bouncing all over BITOG asking the most general and simple of questions ...
Please spend more time reading the existing information and less time posting.