Volvo 240 1991 Owner's Manual page 81

Volvo 1991 240 Model
Other factors which decrease gas mileage are:
Worn or dirty spark plugs
Incorrect spark plug gap
Dirty air filter
Incorrect valve clearance
Incorrect idle speed
Dirty engine oil and clogged oil filter
Dragging brakes
Incorrect front end alignment
Low tire pressure
Shift indicator light
(manual transmission models only)
The Volvo shift indicator light (S.I.L.) is a device designed to help you get even better gas mileage from
your Volvo car. Studies have shown that the best fuel economy is obtained by shifting gears at low
engine rpm and high relative engine load. The Volvo S.I.L. is calibrated to show you when to shift for
improved mileage without sacrificing smooth acceleration .
Use of the S.I.L. is simple. Shift to next higher gear as soon as the light comes on. You may find after
using the S.I.L. for some time that your natural shifting rhythm will adapt to the S.I.L.'s suggestion.
Some drivers may even shift before the light comes on.
Obviously, there will be times when you need to shift later than the light would indicate (for example,
when climbing hills or trailer towing). Using the light regularly, however, should result in a mileage
improvement of six percent or more, depending on how you normally drive.
Programming instructions for shift indicator
If the current supply to the control unit is cut (battery disconnected), the control unit will have to be re-
programmed as the control unit memory will be erased.
Drive the car in each gear (first gear not necessary) for approximately 8 seconds.
The gear change indicator light will flicker once (0.5 seconds), as each gear is programmed.
file:///K|/ownersdocs/1991/1991_240/91240_09.htm (4 of 5)12/30/2006 8:57:13 AM