Air Pump?
 

Morning; I am new to this forum, and my name is Scott. I came here to get help with my wifes 99 Intrigue. It is a fine car with the 3.5L V6 and around 137,000 miles on the clock.
I do need to get some advice on a pump (I am not sure what it is) that runs usually in 3's. It will run and shut off 3X's as you start and/or drive the car. The pump will affect the RPM's, as you can feel it pull the car down, but just for a second. This pump is located in the front left corner of the engine well and it is buried, as I can not see it. When the pump starts it winds up like a turbine...I first told my wife it was a turbo...Ha Ha. All joking a side, I just need to know what is happening here. Should this pump be on and if it is what is it doing? I purchased a "dummy book" due to this being the first Old's that we have had, but it has been no help. There is a "Service Engine Soon" light on, but I have not scanned for codes. I am going to get a code scanner today and see what I find. When I get a code can someone direct me to a code list so I can fix her ride?
Well Thanks for reading my post and I hope we can get Laney's car fixed before she starts to drive my car.....