Short answer, because somewhere on that engine block are the initials GM.
Seriously, start with the easy and eliminate:
No, ..
Start checking out your engine and transmission mounts. Check the rubber to make sure it isn't torn.
under the hood by the engine
no. your engine fits 1995-1999
it should
how to locate engine coolant temperature sensor on a 1999 Cadillac De Ville Concurs
The check engine light on a 1999 Cadillac DeVille can be reset by disconnecting the battery for 30 seconds. The light will immediately come back on if the problem still exists.
10w30 Your oil cap on the engine block will have it printed.
The 1999 Cadillac thermostat can be found on the front of the engine. The thermostat will be inside of the thermostat housing. You can follow the top radiator hose directly to the thermostat housing.
Northstar engine is rated at either 280 for the SLS or 300 for the STS for 1999.
Not directly. There are fuses for the engine computer and it is what turns the light on.Not directly. There are fuses for the engine computer and it is what turns the light on.
front of the transmission--between engine and transmission