I was thinking of it now, Is it possible that this can be caused due to my Catalytic Converter?

See, the story behind that goes like this. Around a year ago I went to the stealer just to give my X a full check up. according to them my Catalytic Converter was bad and it HAD to be replaced. They wanted $1200 for the job. I told them ill look into it. After going to 4 different WELL known indys in my area they all said at the time that it they both seem to be fine. There is no rattling and there is no SES light so just ignore what they said.

Now its been a year and I am thinking, could that be related somehow to this issue? Since the entire time I have had this issue? :/

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Some Of My Mods:


Some Of My Mods In Text:
1. Depo Headlights
2. Weathertech Window Guards
3. eBay/Sony Rear DVD Players
4. JVC NX7000 Navigation System

NOTE: IF anyone likes these mods and needs some help with installing them on their X5s, please feel free to PM me, I am more then happy to help!