Open loop due to system failure

[Zintax]

Hi guys,i just joined, i am one volvo fan i had cars since 2006,short to say i scan car it shows open loop due to system failure,the codes were P0301,P0302,P300,any help i ll apreciate it,i changed plugs,and coils,and fuel injectors

[SuperHerman]

It appears you have a 2008, which is a different platform. That said I suggest you look up how to run the onboard diagnostic testing, I assume the 2008 has this feature, but I don't know. If it does the onboard diagnostic will tell you if certain modules are communicating properly. Report back with your results. It is possible to narrow down the issue by learning which module is having issues and then back tracking from there.

Unfortunately I have no idea what your scanner is providing you information wise. I do know that it is not providing you any useful information as it is not specific enough. A dedicated Volvo scanner or better yet VIDA would be of more use.

It would help if you could provide some vehicle history like miles, symptoms, history of symptoms and work performed and results. It may be a matter of you not connecting a harness correctly.