ford 2.5 turbo auto excelsior motor home?

no engine revs when acc pedal pressed, found water in the multi pin socket next to pedal assy treated with wd cured prob for a few weeks. the engine now revs up but over revs & surges with foot off pedal, eventually goes to normal tick over but wont rev up again eng management light shows. should i replace the pedal assy or delv further ?