My 1997 cadillac deville concours is holding to much pressure in the coolant system and causing my idle to run high, it has a new radiator and theremostat once I releive the pressure every time I drive it the idle will go down but I have to do this everyday

Asked by Jun 22, 2017 at 10:16 PM about the 1997 Cadillac DeVille Concours Sedan FWD

Question type: Maintenance & Repair

4 Answers


Cooling system pressure is not connect to the idle speed. If the pressure is too high the radiator cap may be defective. If the car is running hot you probably need to have the cooling system serviced.

1 of 1 people found this helpful.

If you have a Northstar engine the head gaskets may be leaking.


These older Caddies would raise the idle speed up if the sensors detected an overheat trying to move coolant faster through the radiator, and F_O_R is absolutely correct about the cap, it should vent any pressure over it's rating listed on the cap. Replacing the cap would be the quickest way to see if that elemanates the problem, but if it don't then a head gasket test is the next step.

Best Answer Mark helpful

Thanks for the best answer points, hop it was just the cap.

Your Answer


Looking for a Used DeVille in your area?

CarGurus has 1,496 nationwide DeVille listings starting at $1,999.


Cadillac DeVille Experts

  • #1
  • #2
  • #3
View All

Related Models For Sale

Used Chevrolet Impala
580 Great Deals out of 34,544 listings starting at $900
Used Lincoln Town Car
27 Great Deals out of 1,686 listings starting at $1,099
Used Mercedes-Benz S-Class
160 Great Deals out of 8,097 listings starting at $1,200
Used Lincoln Continental
19 Great Deals out of 3,449 listings starting at $32,794
Used Chevrolet Tahoe
828 Great Deals out of 42,175 listings starting at $1,987
Used Chevrolet Camaro
455 Great Deals out of 31,823 listings starting at $1,450

Used Cars For Sale

2005 Cadillac DeVille For Sale
239 listings starting at $2,495
2003 Cadillac DeVille For Sale
175 listings starting at $2,499
2002 Cadillac DeVille For Sale
188 listings starting at $5,900

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.