E93 325i rough idle and cuts out-help!

[Baked_bean]

Hi all,

Sorry if this is the wrong forum.

My parents have an e93 325i (2008, so I believe it is an N53 engine).

The car has started to run rough and the idle would surge slightly and now it won’t idle and requires throttle to keep the engine running. Any ideas what this maybe?

Thier local garage (whom I don’t trust) have plugged it into the diagnostics they have and it mentions issues with the Catalytic converter?

Thanks in advance.

[bmwmike]

Need the codes but likely problems are spark plugs, coilpacks, injectors, high pressure fuel pump.

Cats unlikely indeed.

[SebringMan]

If it is the cats I'd expect there to be a performance loss.

[happychap]

Out of interest, has the oil been topped up at about the same time it started to play up. I had similar issues following an oil top up and I discovered I hadn't tightened the cap down correctly resulting in some oil on the cover and running rough.