Hi all,

I recently bought a Focus RS MK1 2002 with a performance manifold and exhaust running the original Cat. I have just put a decat on which has turned the car into a bit of an animal. I was advised that the car was set up using a Bluefin Map but the MIL light has come on on my way home this evening so I'm assuming it's because of the Decat. I will be putting the error code reader on later on but thought I'd get peoples opinion on here aswell. If it turns out to be on due to the Decat, can I turn this this off without having to get the car remapped as I believe the car has already gone down this route? Will the light being on have any effect on the running of the car i.e limp home mode etc. I will say the car seems to be spot on at the moment running wise, boosting and holding fine.

Any help or comments would be appreciated.

Cheers
Dave

 

If its the old bluefin map (really old) then it isn't setup for decat,

Check the fault code though and see if it is related to the post cat lambda or cat efficiency threshold

 

I would say the rear O2 sensor is switching as the Cat has been removed

 

Same as on my MK2 ST225, I am going to make an o2 cheater using resistor and capacitor, you can get instructions online for it. Just plugs in between second o2 sensor and loom. Alternatively you can get lambda extension from here http://kalmar-union.com/parts/ford-focus-exhausts/ moves the sensor away from the flow of exhaust gasses so adjusts what it is reading.

 

Change the map or look out fit a miliminator on the bay