15 Plate Fiesta Red Edition Oil Dilution w/ Fuel

[Wadey_56]

My 15 plate Fiesta 1.0 Zetec S Red Edition has recently (past month or 2) developed a problem with the oil tank overfilling and being diluted with fuel. The local garage recommended to take this to Ford for diagnostic as they weren’t able to do it. The oil will need draining and replaced roughly every 3-4 weeks if I let it continue due to the leak. 
 

I've taken it to a Ford garage today and essentially wasted £95 for them to tell me they cannot work on it due to several suspected reasons, it’s got a cold air intake (I installed this about 3 years ago), they suspect there is no catalytic converter (this has not been removed and shocked this was suggested) and suspected the engine had been mapped (it’s not been mapped). I explained the latter 2 were not correct and they refused to do any work to help me solve the issue and recommended I go to a mapping specialist? I find this so frustrating since this issue has only started recently and nothing has been changed on the car.

 

I’ve seen a few forms regarding similar issues but I am not sure what to tackle first, which will be the cheapest. I feel like the issue started around about getting it serviced, but this may be coincident. I did have a fault a while back regarding idle bank 1 being too rich, but this never came back after being cleared. It also had the O2 sensor replaced near the cat within the last 12 months due to heavy fuel ratio which then passed emissions. 
 

I can put the factory air filter back in as a first step and will try new fuel injectors but has anyone had this problem recently / know of the most common faults?

[Tizer]

The High Pressure Fuel Pump may be leaking Petrol back into the Engine.