stuartinzg
Active member
Ok - just worth noting the JB4 only hides the error and cats do not show as ready (AFAIK) although you may already know this. If the MOT station do a DME read out for readiness of the cats, it will fail. There is a DP fix you can buy from AR design in the US and put on, it's a small resistor which you plugin to the DME, it marks the cats as ready but makes the car run really rich, so you only want to do that for the MOT.
Friend of mine here fabricates machines for the pharma business - he re-uses his CNC machines to make exhausts... (hobby), and he made his own catless DPs with the lambda hole at an angle facing backward, plus further out - he only gets a CEL every 6 months or so, but he's running an S65 in the M3 which apparently isn't as sensitive as the lambda on the N54. Pretty much impossible to "trick it", according to n54tech forums.
This is why I haven't bothered with the DPs yet - it's too much labour to change twice a year. If you do manage, please let me know how
Friend of mine here fabricates machines for the pharma business - he re-uses his CNC machines to make exhausts... (hobby), and he made his own catless DPs with the lambda hole at an angle facing backward, plus further out - he only gets a CEL every 6 months or so, but he's running an S65 in the M3 which apparently isn't as sensitive as the lambda on the N54. Pretty much impossible to "trick it", according to n54tech forums.
This is why I haven't bothered with the DPs yet - it's too much labour to change twice a year. If you do manage, please let me know how
