First I need to know does it show a code? You need to have your vehicle scanned for codes. If there is no codes the first thing I would check is the EGR to ensure they are not stuck in the open position. Second I would check o2 sensor. if good the I would check main fuel filter under the car on the underside on passenger side near exhaust and make sure not clogged. if not them only one thing air ildler motor on throttle body dirty and needs to be cleaned or replaced.
_________________________
JR