Here the story:

Last Saturday, had my valves adjusted, 60k on the clock. Everything went smooth car ran tighter than before, No CEL after the adjustment. Drove 30 miles, stopped for about 3 hours, got back into my car, Surprise CEL, Car ran with no problems. Disconected Battery, CEL gone. Drove about 120 miles toward home. No problems. The next day I start up my car , started without CEL, then after about 5 mins idle, CEL on. So i went to Autozone , had car diagnosed , threw P0411 code, which was air injector leak or something, he cleared the code, car ran fine for a day. Now CEL back again.

Help appreciated, thanks

 

I'll bet when they did the valve thing, they inadvertently disconnected one of the vacuum lines. Go to this thread and trace everything:
https://www.s2ki.com/forums/showthread.php?s=&threadid=105368

 

XVIPER, you are right again, The vacuum lines below the injector covers were disconected. Will see how car is running and I will update. Thanks

 

This has happened more than once. You take the car in to get some kind of engine work done and they disconnect one or both of those hoses and don't put it back. Frustrates the heck out of the customer.