I have a 2002 Mazda Millenia 2.5L
My father and I did a tune up in my car two months ago. Since then I drove3,000 miles and just recently got a check engine light. I took the car to Autozone where they read the codes and one of the codes was P1250 (forgot the other one). I came home and stared doing some research then when looked under the hoodof the carI noticed that we had left the solenoid valve (the one with the mitsubishi logo with the vacum lines)unpluged.

My question iscould the car have suffered any permanent damageafter drivinng itfor 3,000 miles with the solenoid valve unplugged?

Also, why did it take so long for the check engine light to come on?

Thank you