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350matt, Mechanical Engineer
Category: Porsche
Satisfied Customers: 20360
Experience:  BEng Hons, worked in the car industry for the last 22 years
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I have opened up my cats on my 997 and emptied them. It

Customer Question

Hi, I have opened up my cats on my 997 and emptied them. It all works fine but the engine light comes on. I've had this removed but after a few days it comes back on, why?
Thanks ray
Submitted: 6 months ago.
Category: Porsche
Expert:  Shantal-Mod replied 6 months ago.
Hello Ray,
I'm Shantal and I'm a moderator for this topic.
I've been working hard to find a Professional to assist you with your question, but sometimes finding the right Professional can take a little longer than expected.
I was checking to see if you had already found your answer or if you still need assistance from one of the Professionals.
Please let me know if you wish to continue waiting or if you would like for us to close your question?
Thank you,
Expert:  350matt replied 6 months ago.
Hello Ray you don't say what year the car is but whats most likely is the ECU is flagging up the lack of a cataylst as there's a post cat O2 sensor whose primary role is to check the efficacy of the cat to disable this OBD function then it will need the services of a custom re-map to turn off the fault code or re-fit a cataylst
Expert:  350matt replied 6 months ago.
Hido you still need help?Bear in mind that the site takes a deposit from you at the beginning and this is held by the site until you rate my answer at which point the cash is split between the site and the expert. I am only paid for my work on this question if you rate my answer, using the star system at the top of the screen. Please do not forget! Thank you

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