Chevrolet Repair: warning signals, vacuum leak, cap etc

Question
I have a 2001 silverado p.u.
My (service engine light ) has come on and will not go off.
I have checked all fluids and all seem fine

Answer
Hello Ola,
Something has set a code in the computer.
A scan tool needs to be used to read the codes, and then appropriate repairs made prior to erasing the code.
There are pages of possibilities, like a vacuum leak, exhaust system problem, fuel mix problem, loose gas cap, etc.
Take it to the dealer, or an experienced mechanic with the correct tools.

Van