My car is a 91 LS 400 & it drinking gas like crazy & has no power to climb hills

 

One of your igniter may be bad. You have to igniter on right on top of thermostat housing and the another one by the A/C compressor. The igniter/coil send the high voltage to the distributor to fire the spark plugs if one of them goes bad you loss power to 4 cylinders out of 8.