The normal oil pressure for a Pentastar engine is typically around 25 to 35 PSI while the engine is running and idle. The exact amount can vary depending on the specific vehicle, but it should always be in this range. If your Pentastar's oil pressure drops below 20 PSI or rises above 40 PSI, then there may be an issue with your engine and further diagnosis will be needed. It's important to check your oil level regularly as low levels of oil can lead to decreased lubrication and increased wear on internal parts that could result in reduced performance or even engine failure if left unchecked. If the oil level looks good but you're still seeing abnormal pressures then a professional should inspect it immediately as this could indicate serious problems with the motor.