[kmf4107]

Is there any blockage in the orifice going to the alarm sender? Maybe have him do a backwards flush from that actual port. Use good fresh oil when you do it and run at least a quart through there at some pressure. I had a tyranny do that once and it cleared out a piece of crap and everything started working again.

During the replacement of the sensor the second time the mechanic did clean out the tube/orifice leading to the sensor, it again silenced quickly on start up for a couple of starts and then reverted back to the same extended alarm. Interestingly at the end of season after oil change it silenced in a few seconds but after that same problem.