By bad intake do you mean cracked air intake manifolds?I've had intermitted issues since i bought mine had bad intake issue, maf and dpf cycle issues, random RP but mainly at top end RP.
Last year I dismantled the intake between the V where the 2 EGR pipes go in and they were completely blocked up like golf balls of soot on each side. If you had issues with air fuel mix this could be helpful.
EGR should be being used at that speed going steady, long shot but its been a year without issue for me now im so happy.
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