2000 Cadillac Seville Q&A
2000 Cadillac Seville Question: check engine light on
I would have to see the codes listed. To have so many codes either a common power or ground to several sensors or the computer has high resistance, the computer may be at fault of you have damaged wiring (inspect the wiring for rodent damage, abrasion, burned wires ect.....). Start the engine let it run. Wiggle the wiring harness and see if the engine suddenly runs rough, if so closely inspect the electrical connections and harnesses where you were touching when the idle speed changed or engine ran rough. - patrick mannion
A check engine light that intermittantly comes on tells me at times the computer is happy with the test it did at times, and others it is not satisfied with it's test results. The codes could be related. May, but I doubt it, have just one problem. If I were you, I would clear the code. Then drive the vehicle until the check engine light comes on. Immediately check the code, It will then tell you what was set. Now, this may be the tip of the iceberg, there may be, once the problem is properly repaired, more codes to come. - Visitor
Would look at all codes,and check the worst one's. Some codes will triger others.Do you know what the codes are thanks Brian - Visitor
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...
...mputer, change the oil had the tiimng checked and it does not have any codes showing up and NO CHECK ENGINE light on...
The EGR control solenoid or EGR valve may fail causing the Check Engine Light to illuminate.
Illumination of the Check Engine Light may be the result of a loose or worn gas cap.
The crankshaft position sensor may fail causing the engine to stall intermittently, the Check Engine Light may or may not illuminate.