EML: Intake Manifold Runner position sensor/switch circuit range/performance

[DXX]

Yeah - I am surprised how much of a difference it's made to the van having it swapped

I usually do one slow commute of 15 miles a week, then one steady 60mph return trip of around 100-120 miles at the weekend and apparently I'm not working the engine hard enough to prevent this build up

At 57K miles it’s quite likely it’s a jammed / leaking EGR valve that is constantly passing exhaust gases into the induction.