I’ve got a 2011 Mack with an MP7 in the shop with a rough idle, jumping between 600 and 650 RPM and low power. Truck has no fault codes. It’s gotten a new EGR pressure sensor, EGR valve, Fuel pressure relief valve, fuel filters. EGR cooler was clean when checked. Removed and checked for debris in fuel lines going to ECM cooling plate. Fuel pressure jumps around between 50 and 60 PSI at idle.
Any ideas?
2011 Mack MP7 Rough idle, low power
Discussion in 'Heavy Duty Diesel Truck Mechanics Forum' started by springerj, Dec 30, 2021.