Buick regal service engine soon light on - 2000 Buick Regal

That is an emissions code. It means you have a small leak in one of the lines. Most likely it the line that goes from the engine to the evap canister in the drivers side rear inner fender well.

Disconnect the negative battery cable for 30 minutes. Reconnect after and the code will clear. However if the problem persists, the code will come back with in 20 miles or 30 minutes.

Was the oil changed?

with a scanner buttttt,,, if the light is on theres a problem that needs to be addressed

Pull the instrument panel out and check the bulb that operates that light.

Here are some possible causes and fixes http://www.obd-codes.com/p0440

It is most likely a crank sensor!!!!!!! i am 99.9999% positive that this is the culprit. I am a mechanic and this is the first thing i would check with your description.

you need to find someone with an old type scan tool,or one that has an adapter for the older cars to read the codes. you can also do this by jumping 2 wires on tha obd connector and count the flashes. the first suggestion is the best. get the code and get back to me and we'll go from there. hope this helps Thanks Ray

The error that I'm showing for error code P1133 is 
P1133 Heated Oxygen Sensor (HO2S) insufficient switching bank 1 sensor 1(Rear Bank).  I would suggest having both of your Oxygen Sensors replaced if you haven't already had that done.  Hope this helps.  Thanks for an honest rating and for using FixYa.

i had auto zone check the computer and was told i needed two sensor and i like know where they are located and if i can installed them my self thank you beepa1