I Had a de-catted full system fitted to my bugeye awhile ago and about a month and a half after the engine light came on.
I had it put on a mate computer and got the code p0420 (cat insufficent Bla Bla) and had the light taken off.

Yep u guess it, the very next day it came back on which u would expect anyway.

About a couple of months after i got him to put it on the comp again cause i forgot the code and the light was again taken off.

Now heres the bit thats thrown me and the bit i just don't get
Its now been 2 weeks and about 200 miles and still no light back on.
I know u people will b saying "whats your problem then" but if the cat has been romoved and the engine light came on to back that up, there is still no cat so why hasn't it come back on.

 

any ideas guys

 

It's down to driving style (I won't pretend to be able to remember the technical bit.....) once off the back roads and onto (say) the motorway, you ease of and cruise at 89 mph with all the reps.... the ecu then tries to run "economically" and finds the cat is "stuffed" so it chucks a CEL.

I ignored mine for nearly a year.

HTH

dunx

 

since the lights stayed off i've only been around town though, giving it large when i can, down bypasses and stuff though.

 

get it remapped and the CEL removed, or fit a CEL fix..

Simon

 

Where do i get this cel fix box from

 

Maplins. Its a 12 pence resistor but I can't currently remember which one I'm afraid.

 

That resister fix is not for that sensor.

Thats for if i change the up pipe which i haven't.