Cadillac DeVille Problem Report
Cadillac DeVille Check Engine Light Due to Intake Manifold Vacuum Leaks
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.
Diagnostic scan check - found engine misfire due to Intake Manifold Cracked and Leaking.
No work performed at this time. - MMB1968
Cracked Intake Manifold was causing a misfire. It was Replaced with an Aftermarket Dorman intake. (Least expensive option) - Visitor
check engine light comes on while driving - vandy
I have a 98 Cadillac Deville with a Northstar motor. It has been running hot. I changed the the...
the car quit had to replace the whole fuel pump. since then the service engine light is on. i h...
The EGR control solenoid or EGR valve may fail causing the Check Engine Light to illuminate.