1. I dont know why or hat happen just all of a sudden one day my crusie control stoped working.... I have had a mechanic work on it were he had to take it out before but i cant say its his fault cause im not sure.... any suggestion?

2. Sometimes my car will idel different... its usually about @ a 1000rpms but sometimes it drops down to about 450rpms and goes back up and it does this simaltaniously.... fuel injectors?

 

#2 what year and how many miles

 

92-95 model with swapped out d15b with around 65 tho

 

if you didnt change out the vacuum hoses, then i would say it is that.
if you did, then probably it is the idle air control valve or also called electronic air control valve.
had the same problem and it was the vacuum hoses. cost bout 2 to 3 dollars (did not worry about the big one off of the brake booster)

and in additional to the above - i also have a bad IACV (eavc)