What are these solenoids?

[DemonGT]

What are these for on passanger side, back of strut tower?

 

[91AOD5.0LX]

EGR control Solenoid….
LMR gives a good description of what it does. I will post their write up:
Hope this helps….

https://lmr.com/item/LRS-9459A/1987-1993-mustang-egr-control-solenoid?utm_source=google&utm_medium=cpc&adpos=&scid=scplp&sc_intid=&gclid=CjwKCAiA1-6sBhAoEiwArqlGPp7xsXW-3EZM0p8UzE7E3o_uRMhDiX6HzMPZMiK25uLFnaPNllMznRoCtIMQAvD_BwE

 

[DemonGT]

What about all the junk under the EGR solenoid? Is any of that needed?

My EGR is long gone along with the A/C.

 

[91AOD5.0LX]

What about all the junk under the EGR solenoid? Is any of that needed?

I’m sorry, I don’t know the answer to that for you but I’m sure others can help.
I am interested in knowing as well.

 

[Mcmahst]

Under the EGR control valve are the TAB/TAD solenoids. Those open and close vacuum valves that route air from the air pump.

 

[Mustang5L5]

If your stock H-pipe and cats and air pump are gone, you can delete the TAD/TAB solenoid. I remove it all and cap the vac source line.