check the 3 hard plastic vacuum lines on the passanger side of the engine.that run from the fender,under the air intake tube, to the engine.if there's a loom covering them,remove that,check for leaks or breaks,fix as needed.
my light used to flash while crusing around 25-35 mph,then go off past that.fixed those broken line's,no more light.this MAY be the problem.i suggest you pull the codes.