vacuum switch bringing on engine light only at start up E175EXECD

[Jerry T]

What would you look for at this problem...I put a small pressure on hose of vaccum switch and the engine light did not come on When it starts it comes on and then resets and every start after that is good no engine light . Only after it sits for a while does the vacuum switch bring on the light and horn Where do I start?

 

[Rwbutler]

What would you look for at this problem...I put a small pressure on hose of vaccum switch and the engine light did not come on When it starts it comes on and then resets and every start after that is good no engine light . Only after it sits for a while does the vacuum switch bring on the light and horn Where do I start?

Disconnect vacuum switch wiring,rerun, if problem still exists,ckeck wiring and tachometer.
If problem does not reappear,,check switch,check fuel system for restrictions.