A lot of men get embarassed when told, correctly, about an engineering item, by a woman.
Years ago, my next door neighbour and I set up his wife to do just that.
Every time that his car went in for service it came back with the ignition timing so badly retarded that it ran on after switching off. (Obviously the mechanics could not /would not read the BMC service manual ).
So instead of correcting the timing, and resetting mixture and idle speed, (again ) we told her what to say. She drove the car into the shop, and asked for the Service Manager. When he appeared, she then told him what was wrong after the service, adding "It shouldn't take more than ten minutes to put it right. I'll wait while you do it" The shop was silent after the noise of his jaw hitting the floor!
Since it was the last service in warranty, we did all the following services!
Howard