156 2.4 JTD 10v engine management warning on acceleration.
Ever since I've owned my 156, when accelerating from lowish revs (especially in 4th and top) the engine management warning comes on and momentarily cuts the revs - which can be a little hairy when overtaking. It will sometimes do it in third but generally you can rev through it. I spoke to a mapping (specialist?) the other day who was particularly unhelpful and he said there was nothing he could do (or I suspect couldn't be bothered to do).
Any ideas, suggestions please?