service indicator FORD SIERRA 1991 2.G Reference Workshop Manual

Note:Due to the complexity of the automatic transmission, it is difficult
for the home mechanic to properly diagnose and service this unit. For
problems other than the following, the vehicle should be taken to a
dealer service department or automatic transmission specialist.
Fluid leakage
MAutomatic transmission fluid is usually deep red in colour. Fluid
leaks should not be confused with engine oil, which can easily be
blown onto the transmission by air flow.
MTo determine the source of a leak, first remove all built-up dirt and
grime from the transmission housing and surrounding areas, using a
degreasing agent or by steam-cleaning. Drive the vehicle at low speed,
so that air flow will not blow the leak far from its source. Raise and
support the vehicle, and determine where the leak is coming from. The
following are common areas of leakage.
a)Fluid pan ( transmission “sump”).
b)Dipstick tube (Chapter 1).
c)Transmission-to-fluid cooler fluid pipes/unions (Chapter 7).
Transmission fluid brown, or has burned smell
MTransmission fluid level low, or fluid in need of renewal (Chapter 1).
General gear selection problems
MThe most likely cause of gear selection problems is a faulty or
poorly-adjusted gear selector mechanism. The following are common
problems associated with a faulty selector mechanism.
a)Engine starting in gears other than Park or Neutral.
b)Indicator on gear selector lever pointing to a gear other than the
one actually being used.
c)Vehicle moves when in Park or Neutral.
d)Poor gear shift quality, or erratic gear changes.
MRefer any problems to a Ford dealer, or transmission specialist.
Transmission will not downshift (kickdown) with
accelerator pedal fully depressed
MLow transmission fluid level (Chapter 1).
MIncorrect selector adjustment (Chapter 7).
Noisy in neutral with engine running
MInput shaft bearings worn (noise apparent with clutch pedal
released, but not when depressed) (Chapter 7).*
MClutch release bearing worn (noise apparent with clutch pedal
depressed, possibly less when released) (Chapter 6).
Noisy in one particular gear
MWorn, damaged or chipped gear teeth (Chapter 7).*
Difficulty engaging gears
MClutch fault (Chapter 6).
MWorn or damaged gear linkage (Chapter 7).
MWorn synchroniser units (Chapter 7).*
Jumps out of gear
MWorn or damaged gear linkage (Chapter 7).MWorn synchroniser units (Chapter 7).*
MWorn selector forks (Chapter 7).*
Vibration
MLack of oil (Chapter 1).
MWorn bearings (Chapter 7).*
Lubricant leaks
MLeaking oil seal (Chapter 7).
MLeaking housing joint (Chapter 7).*
*Although the corrective action necessary to remedy the symptoms
described is beyond the scope of the home mechanic, the above
information should be helpful in isolating the cause of the condition, so
that the owner can communicate clearly with a professional mechanic.
Pedal travels to floor - no pressure or very little
resistance
MBadly stretched or broken cable (Chapter 6).
MStripped pawl on pedal (Chapter 6).
MBroken clutch release bearing or arm (Chapter 6).
MBroken diaphragm spring in clutch pressure plate (Chapter 6).
Clutch fails to disengage (unable to select gears)
MCable free play excessive (Chapter 6).
MClutch driven plate sticking on gearbox input shaft splines
(Chapter 6).
MClutch driven plate sticking to flywheel or pressure plate (Chapter 6).
MFaulty pressure plate assembly (Chapter 6).
MClutch release mechanism worn or incorrectly assembled (Chapter 6).
Clutch slips (engine speed increases, with no
increase in vehicle speed)
MClutch driven plate linings excessively worn (Chapter 6).MClutch driven plate linings contaminated with oil or grease (Chapter 6).
MFaulty pressure plate or weak diaphragm spring (Chapter 6).
Judder as clutch is engaged
MClutch driven plate linings contaminated with oil or grease (Chapter 6).
MClutch driven plate linings excessively worn (Chapter 6).
MFaulty or distorted pressure plate or diaphragm spring (Chapter 6).
MWorn or loose engine or gearbox mountings (Chapter 2).
MClutch driven plate hub or gearbox input shaft splines worn
(Chapter 6).
Noise when depressing or releasing clutch pedal
MWorn clutch release bearing (Chapter 6).
MWorn or dry clutch pedal pivot (Chapter 6).
MFaulty pressure plate assembly (Chapter 6).
MPressure plate diaphragm spring broken (Chapter 6).
MBroken clutch driven plate cushioning springs (Chapter 6).
REF•14Fault diagnosis
Clutch
Manual gearbox
Automatic transmission