1999 trooper 3.5L engine with torque on demand. runs smooth but the rear wheels on the torque-on-demand panel blink and so does the red "CHECK" light. while the RPMs are normal-y-ish, i'm actually getting about 5-6 miles per gallon of gas. no spit. 5 mpg. plugs are good and platinum, but have a white ash on the prong side of the sparkplugs. thanks in advance -jack

 

More details! Do you know if it is locked in four wheel? Also does it start easy? Maybe economy is poor from one problem and the TOD flashes are a different concern.