An intake manifold vacuum leak can develop from a variety of sources, often causing illumination of the Check Engine Light with codes P0171 & P0174 stored. Thorough diagnoses will be necessary to pinpoint the cause in order to make the correct repairs. A "smoke" machine is often used to isolate the cause of difficult to find vacuum leaks.
Check Engine Light Due to Intake Manifold Vacuum Leaks on Cadillac Seville SLS
Average mileage: 111,600 (59,000–143,000)
18 people reported this problem
3 people shared problem details
2001 Cadillac Seville SLS143,000Visitor
Found a hose was not plugged in, plugged it back in. Error code went away in about 10 seconds.
2003 Cadillac Seville SLS59,000Visitor
intake boot cracked due to bad front motor mounts
A Loose or worn gas cap may cause Check Engine Light to illuminate.
The torque converter clutch (TTC) may stop working due to an internal transmission failure. The...
The water pump and/or the plastic side tanks on the radiator may leak causing a loss of coolant...
The crankshaft position sensor may fail causing the engine to stall intermittently, the Check E...
The EGR valve may stick open, causing a rough idle and/or the Check Engine Light to illuminate.