: Northstar Gas Mileage

09-22-08, 06:33 AM
Anyone out there track their mileage on a 2003- 2005 DTS.
Canadian RATINGS claim a 13.4/8 L/100 OR 21/35 MPG
The best I can do is 10.9 if I drive it 95-100 and I jump to 14.5- 15 aqround 120 kph.
If I put my foot into it and run 130 -135 kph it drops back down to 11.3 - 11.7.
Input anyone.:worship:

09-22-08, 09:35 AM
You should be getting close to double the mileage at 100kph.......but remember that the DTS has a final drive ratio of 3.71:1, so will get 2 - 4 mpg less than a base or DHS. Your engine should turn about 2100-2200 rpm @ 110kph +/-.

Remove the engine cover and pull the vacuum line off the fuel pressure regulator (FPR) located on the (looking at the engine) right rear of the fuel rail. Is there any gas in the line or in the nipple on the FPR ? If there is, easy fix from www.rockauto.com or parts at Lindsay Cadillac, Luke, parts, ------> over there.