Thanks for your help guys. I removed the switch and cleaned it. Put it back in and it worked fine !!!! It was in fact 19mm. If I can't cancel the one I ordered I will keep it for later in case it gives problems again.
When I removed it there was a sudden release of gas. It lasted a few seconds ????? Car was cool did not drive it all of last week.
It was only a 10 minute job. Thanks again for your help guys you saved me 100 euro or so
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