Early this morning i drove from Birmingham to London in the pouring rain. After around two hours of wet motorway driving, i reached the 40mph section at the end of the M3. This has a set of traffic lights - thus the first actual "stop" for many a mile.

Unfortunately i noticed that the engine idle speed seemed to have become 3000+rpm. Hooking your foot under the accelerator pedal made no difference, so i spend the whole of the crawl into Putney with drivers to my side thinking that i wanted to race them .

By the time i got to Putney, things had settled down, and tickover was below 1000rpm.

Any ideas as to what caused the idle speed of the engine to increase so much - could somethings have got wet that shouldn't have?

mb

(Cross posted on 22B)