If a Check Engine Light illuminates indicating leak detection pump (LDP) failure, the cause is often pinched or disconnected vacuum lines to the pump. Vacuum lines should be inspected before replacing the leak detection pump. Contamination (carbon or debris) in the pump can cause failure and any hoses should be cleared before a new pump is installed.
Car Problem Reports
Dodge Ram 1500 Check Engine Light Due to Pinched Leak Detection Pump Vacuum Lines
Dodge Ram 1500 Problem
Exhaust & Emissions Affected: Gasoline
Average Mileage: 116,814 mi (79,478 mi - 179,000 mi)
Was informed I needed a NVLD pump and a PCV valve. Total maintainance $250
Visitor, 2002 Dodge Ram 1500, 79,478 mi
engine light on but runs fine heard a hissing under the truck and found two air lines cracked and part of the line missing when I took the lines off the crumbled in my hand much like my dash board I replace the lines and the light went out
Visitor, 2004 Dodge Ram 1500, 80,000 mi
just came on then my pump fell off. I found out later the wirering housing had melted.
Check engine light vacuum lines clogged