I purchased a 1985 Cadillac DeVille Coupe 2dr. Engine air cleaner is reading 4.5. Sticker on cowl panel reads 4.1. I have the identification tag reading from the front rear of the engine block... might that help me tell if its a 4.5 or a 4.1 or not???? Anyway to tell for sure??? If engine is swapped, the original VIN will not help me.... Any idea??? New to the forum... Hope to learn alot!!
Thanks!

I believe the '85's were 4.1. I know my '85 Eldo was. Pretty sure Deville was the same. 4.5 came out around '89.