No one to my knowledge has programmed a solenoid egr controller code or hardware for megasquirt yet. There are outputs you can use with a 12v solenoid and set up AND type fucntions like "if MAP >30 and less than 80, and tps is between a range then ground this output "X" for instance. Then you could use a solenoid. But this setup is so much simpler. What should happen ideally is that between say 20 and 60% throttle the egr should be open and it will displace some air in the cylinders. When I tune the engine on the road it is all based on o2 sensor feedback. Therefore egr should be transparent if set up right.

I did a lot of research comparing the 92 gm EGR and the Camaro obd2 EGR. The 3.1 engine controls EGR based on TPS and RPM. The Camaro uses TPS and MAF. So mine will be just TPS. Both these systems use coolant temp to turn them on, haven't put anything in to disable it before the engine warms up. If it becomes a problem I can add something like that later. Thanks do Dan houlton for advice on these mods he has done most of this on his 3800 and helped me out.