I am reminded of my first Towed car. back before it became a towed car. Oh it was a 1992 Chevy and TBI.
But I had a problem with excessive brake pedal travel. The dealer acknowledged the problem but could not figure it out. They tried like 3 times and still made only a minor improvement.
Finally I took a stab at figuring it out
Sitting at my desk at work a good hundred yards or more from the car.
Next day I drove it to my Tire guy, gave them a SPECIFIC instruction
Drove out they were like new. (Well they were new at least the parts that were out of spec which I told him to inspect).
And the dealer's man is supposed to be FACTORY TRAINED!!!!!!.
(I"m self trained).