'92 Protege

I've had this vehicle trouble free since new. It now has 3 problems
which seem to be related but 2 repair shops cannot figure out.
-The engine check light flickers on after a couple of minutes driving
then goes off.
-The engine races after a couple of minutes at idle, then settles down
again.
-It's starting to stall at stop signs (and red lights)
-If it doesn't fire first time on starting (with the engine hot)it
doesn't want to start again unless you let the engine cool off then
boot the gas.
OK that's 4 - Any ideas?

Phil