1997 bmw e39 540i running rich

[120alexis]

I have a 1997 bmw 540i and i think it is running rich sometimes it just starts shaking randomly and exhuast smells bad like raw fuel what can it be ?

[StRaNgEdAyS]

One possibility is you have some intermittent coil fault.
Scanning the car to see what codes are being generated is always a good start.

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[120alexis]

I already did spark plugs and has no codes put in some bosh. It also sometimes smells like unburnt fuel

[JimLev]

What did your old plugs look like?
How many miles on the car?
Could be the CAT's are on the verge of crapping out.

[120alexis]

Has 161 k miles. Old spark plugs were some cheap autolites they looked like the car was running a little rich.

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Looks like the cats on the car were previously changed.