Hi all, I have a 2018 focus 1.0 ecoboost. It was in the Ford dealership for a new vacuum pump. But when I got it back home the oil light started flashing and the eml light came on. Got the rac out because the engine was making a rattling noise. But oil level was maximum. Can anyone tell me if the vacuum pump could have caused the problem. 

Driving with the oil pressure light on when you don't know the cause is about the worst thing you can do to an engine. Just because your oil is topped up, it doesn't mean the pump is working and that the pressure has built up.

If I remember correctly the vacuum pump is driven off one of the camshafts. I would've thought if it seized up or something it would cause the timing belt go and completely knacker the engine rather than just low oil pressure. You might be lucky and the rattling noise might be the vacuum pump, or it was a pure coincidence and you now need a new engine.

I have never had any problems with the oil pump until the Ford dealership fitted the new vacuum pump 

And the rattling noise only started when the new vacuum pump was installed 

No reason that fitting a new vacuum pump should cause a problem with oil pressure.

The 1.0 ecoboost engine can go from fully working to a pile of scrap metal in less than 5 minutes if the oil pressure fails. Don't run the engine until you have the oil pressure fault checked, what mileage has the car done ?

51000

 

9 hours ago, Steph.johnston said:

51000

hardley any miles, the engine should be good for double that without major problems. I think you should get back in touch with the dealer and see what they say about the matter. There is no reason that the work you had done should be causing oil pressure issues, and if a pipe had been disconnected and left off then there would be oil everywhere. From what you have said there isn't oil leaking so it does seem to be a pure 'pressure' problem. The mileage is not high enough to suspect that the wet timing belt is falling apart and blocking the oil strainer in the sump (does happen but normally on much higher mileage). The actual oil pump can be an issue on these engines and I would think that will need checking first.