Why is the rum gone?
Join Date: May 2012
Location: United Kingdom
County: Greater Manchester
If your DPF is in good condition then there should be no reason to have regens removed in the remap.
However, Most DPFs are in OK condition but not 'Good' so you will almost certainly benefit from having it cored.
You will notice more power, smoother response, and improved MPG from coring the DPF.
If you have the Regens written out of your remap then you MUST remove or core the DPF, if you don't, you will get between 200-300 hundred miles before you start to have problems with increased back pressure, very poor performance, reduced MPG and eventually (maybe another 100-200 miles) you will get limp mode and possibly some turbo issues thrown in for good measure.
If you core the DPF and don't have regens written out of the map then you will get all the benefits but still have to endure the smoking and fuel usage (I can't remember the exact figures but I think Fixitsan did the maths and figured regens cost about 1/2% in extra fuel, (so 1/2 a mile per hundred miles reduced fuel economy))
Basically do not have the DPF mapped out if you are not going to have it physically removed, either by a bypass pipe or by drilling out the centre of it.
(the MOT issue is a whole different discussion, if you just drill through the core a few times with a long masonry drill it will still pass the MOT, If you replace it with a bypass pipe it might not pass unless you are friends with the tester)