Hopefully i can help..
According to my info in regards to P3007 On the 4072.0HDI is as follows but is also can be known to be in regards to camshaft sensor failure - no signal so bear that in mind..
Cause :- Mass air flow (MAF) sensor - air flow low
Possible fault :- Wiring/loom connector fault to mass airflow meter / Mass air flow meter itself or pipe work loose or split in regards to intake/check air filter,vaccum system / EGR valve sticking or stuck excess soot build up on valve or exhaust gas recirculation circuit / exhaust system / Possible fault with the ECU
I do hope this helps