: engine swap



GNARLEYSTS
07-24-09, 12:49 AM
I have a 97 STS with a bad motor. I bought a wrecked 99 Deville with low miles on the engine. Is there any reason this engine wont work in my car? I noticed the 97 engine has a 3-prong male plug on the right side bellhousing flange where the 99 engine does not. Do i need this? Thanks for any help.

zonie77
07-24-09, 01:23 AM
What's bad with your current motor?

GNARLEYSTS
07-24-09, 01:49 AM
High miles, 165k, blown head gasket(s). Major leaks. Do you know if the 99 Deville motor is compatible?

zonie77
07-24-09, 02:03 AM
I do not think so.

It's been covered before and you might be able to search for it.

GNARLEYSTS
07-24-09, 02:13 AM
Thanks, Ive been trying, im kinda new at this...

Submariner409
07-24-09, 10:38 AM
Gnarley.........Look at your car's VIN (Vehicle identification Number)......either at the windshield tag or the driver's door sticker. The 8th character is the engine designator......."Y" is the 275 hp/3.11 final drive package and "9" is the 300 hp/3.71 final drive package. They are different in many respects, including engine and transmission electronic controls. An STS must get a VIN "9" replacement engine, and from a year very close to yours. I'll bet the Deville is a VIN "Y". Know that 2000 and up are totally different. No swap.

If the car is otherwise in fine to mint condition it is worth fixing. Where are you ?? It might be better to ship the car to Jake (97EldoCoupe, www.northstarperformance.com) in Canada and have him stud the block and overhaul it.

Click on "user cp" up in the blue bar ^^^ and update your login name with your car, year, mileage, location.......it makes diagnoses easier for everyone when we're all on the same page.

BTW..........Welcome Aboard !!!!! :highfive:

GNARLEYSTS
07-24-09, 10:12 PM
Thank you sub409! Yes my 97 STS is a 9 motor and the other motor i bought is a 99 Y motor. Ive been searching like crazy for info because I was told it would work! The only difference Ive found in the motors is the 3 prong plug by the right side bellhouse flange. The new motor doesnt have it and I cant even find that wire plug on the wire harness on my STS! Grrr....gettin a little frustrated here...but not giving up!

Destroyer
07-25-09, 02:36 AM
I have a 97 STS with a bad motor. I bought a wrecked 99 Deville with low miles on the engine. Is there any reason this engine wont work in my car? I noticed the 97 engine has a 3-prong male plug on the right side bellhousing flange where the 99 engine does not. Do i need this? Thanks for any help.Disposable car that is not worth fixing. Move on.