I finally got around to adjusting the valves in my 280SE, and Tomguy was correct. I was able to make the adjustments with a good crow’s foot attachment so gave up my search for the special tool. Some minor adjustments on all but two valves. Two required a good quarter turn, so glad I made the effort. Easy job, and car ran great afterwards.

However, when I had the air filter housing off I noticed the vacuum hose to the manifold pressure sensor was not clamped to the sensor. An easy tug and it came off. I figured that can’t be right so I clamped it. When I started the car it ran higher rpm than normal. Thinking this was just the cold start valve, I drove it a few miles until up to temperature. It still ran significantly higher idle rpm. Maybe 1200 rpm idling.

I went back and looked at Jerhofer’s pics since his engine was the same and he did such a great job of documenting his work. His car did not have a clamp on the MPS device as best I could tell.

Can anyone explain what caused this condition?
Was the clamp a bad idea?
Put it back the way it was and leave it alone?
Never touch the MPS?
Does not seem a clamp should cause such a change (see pic).

Attached Thumbnails

 

__________________
Ron
1972 280 SE 4.5
2017 Lexus ES 350
2011 Ford Escape
2006 Chevy Silvarado