1991 HONDA CIVIC check engine

Spark Plugs
Spark plugs should be replaced every 24 months or 30,000 miles (48,000 km), whichever comes first.

Recommended spark plugs:

CAUTION:
Never use spark plugs with an improper heat range; they will adversely affect engine performance and durability.
Spark Plug Replacement
Replace plugs one at a time, so you don't get the wires mixed up.1. Clean any dirt from around the spark plug base.
2. Disconnect the plug cap, then remove and discard the old plug.
3. Check the gap of the new spark plug before installation.
Plug gap should be:
1.1 mm (0.04 in)
4. Thread the new spark plug in by hand to prevent cross-threading. 5. After the plug seats against the cylinder head, tighten 1/2 turn with a spark plug wrench to compress the washer.
6. Reinstall the spark plug cap.
CAUTION:
The spark plugs must be securely tightened, but not overtightened. A plug that's too loose can get very hot and possibly damage the
engine; one that's too tight could damage the threads in the
cylinder head. PLUG CAPProCarManuals.comMain Menu s t

Air Conditioner Care

Condenser and Radiator
Check the engine radiator and the air conditioner condenser (in front
of the radiator) for accumulated dirt, insects or leaves. Carefully brush or hose them off to assure maximum cooling performance.
CAUTION:
Radiator and condenser fins are very thin and easily damaged; do
not bend them with the high water pressure or brush.
Compressor Drive Belt
Check the compressor belt tension monthly, during periods when
you use the air conditioner a lot.

If the engine has been running, some engine components may be

hot enough to burn you.

When pushed with 98 N (22 Ib) of force midway between thecompressor drive pulley and the engine crankshaft pulley, the belt
should deflect about:
9.0 — 11.0 mm (0.35 — 0.43 in)

CRANKSHAFTPULLEY

COMPRESSOR DRIVE PULLEYProCarManuals.comMain Menu s t

Jump Starting

To start a car with a dead battery, use another battery of the samevoltage, and the proper jumper cables.
Procedures other than those below could cause injury or
damage from battery acid spray, explosion or charging system

overload.

Never connect the jumper cable directly to the negative post of
the "dead" battery.
Never allow the two cars to touch each other. Never allow the jumper cable clamps to touch each other.
Never lean over the battery when making connections.
Never attempt to jump start a vehicle with a frozen battery. The
battery could rupture and explode. If you suspect a frozenbattery, remove the vent caps and check the fluid. If there
seems to be no fluid, or if you see ice, do not attempt a jump
start until the fluid thaws.

CAUTION:

If jumper cables are connected backwards, the car's main fuse
may blow.
1.Turn off all lights, heater and other electrical loads, set parking brake, and shift the transmission to Neutral or Park.
2. Use one cable to connect the positive terminal of the booster
battery to the positive terminal of the "dead" battery.

3. Use the other cable to connect
the negative terminal of the

booster battery to the engine at
the ground cable as shown.
4. To remove the cables, reverse the above procedures exactly.
DO NOT push or tow a car to start
it. The forward surge when the en- gine starts could cause a collision.
Also, under some conditions, the catalytic converter could be dam- aged. A car equipped with an auto-matic transmission cannot be
started by pushing or towing.
DEAD

BATTERY
Negative to the
engine at the

ground cable, not

to the battery

Do not attach

cable here
Positive to

positive
BOOSTER

BATTERYProCarManuals.comMain Menu s t

If towing is necessary, contact a professional towing service. Your
authorized Honda dealer can assist you with detailed towing

instructions.

Never use tow chains or rope to tow a car; your ability to safely
control the car may be adversely affected.
We recommend the following: Flat Bed Equipment —Entire car is winched on a flat bed vehicle.
This is the best way of transporting your Honda.
Wheel Lift Type—Tow with the front wheels off the ground.

If the car can only be towed with the front wheels on the ground:

make sure the transmission is full of fluid (see pages 78 — 79) and
tow with the transmission in neutral (N) and the ignition key in the 1
position.

CAUTION:

To avoid serious damage on automatic transmission cars, first
start the engine and shift to D4, then to N and shut the engine off. If the engine does not run or the transmission cannot be shifted
while the engine is running, the car must be transported on flat
bed equipment.
Check local regulations for towing.

CAUTION:
Do not exceed 35 mph (55 km/h) or tow for distances of more
than 50 miles (80 km).
If a sling type tow is used, the tow truck driver should position
wood spacer blocks between your car's frame and the chains
and lift straps to avoid damaging the bumper and the body. Do not use the bumpers to lift the car or to support the car's
weight while towing. TowingProCarManuals.comMain Menu s t

Catalytic Converter

A catalytic converter is installed in the exhaust system to help
clean-up the harmful exhaust gases that can cause air pollution.
To be effective, the converter must work at high temperature, so don't park your car over dry grass, leaves or anything else that

could burn easily.

To stay effective, the converter must not be contaminated by

leaded gasoline; use only unleaded gas as explained on page 54.

CAUTION:
The converter can be overheated and damaged if it's fed too much
unburned fuel mixture from the engine, so:
— Don't push or tow the car to start it; if the battery is dead, jump start the car as shown on page 110.
— Don't turn the key off while the engine is running above idle
speed.

— Don't change the ignition timing, or remove any emission control
parts.

— Use only the spark plugs specified in this manual. — Don't keep driving your car if it isn't running properly, or if its CHARGE warning light comes on; have it checked by your
Honda dealer.
CATALYTIC CONVERTERProCarManuals.comMain Menu s t

Index

Battery
Charging System Warning Light.............................................. 30
Jump Starting ........................ 110
Maintenance............................. 89
Specification (Hatchback).... 116
Specification (Sedan)............ 119
Beeper System Fasten Seat Belt Beeper(Sedan).................................. 11

(Hatcback)............................ 15

Belts, Seat............. See "Seat Belts"
Body Repair.................................. 102
Brake Warning Light...................... 31 Brakes
Brake Failure Warning Light.... 31

Brake Fluid................................ 84

Brake System Design.............. 83
Brake Wear Indicators............. 84
Parking Brake........................... 42
Parking Brake Warning Light.. 31
Break-in Period................................. 2

Bulb
Replacement............................
92

Specification (Hatchback)....
117
Specification (Sedan)............

120
Buzzer........... See
"Beeper System"
Capacities (Hatchback)............... 115 Capacities (Sedan)....................... 118
Care and Cleaning.......................... 99
Catalytic Converter..................... 126 Certification Label....................... 121
Chains, Tires...................................

95
Check Engine
Warning Light......... 31
Child Proof Door Locks...................

5

Child Restraint
System................. 21
Cigarette Lighter............................ 44

Clock............................................... 42
Clutch Pedal Adjustment.............. 61
Compact Spare Tire.................... 104
Coolant Temperature Gauge ........

28
Cooling (with
A/C).........................

49

Cooling System..............................

80

Crankcase Emission Control
System................................... 124
Cruise Control Operation.................................. 39
Indicator.................................... 31

Defogger........................................ 34
Defroster........................................ 51

Doors
Child Proof Door Locks............. 5

Locks........................................... 3

Power Locks.............................. 4

Emergency
Changing a Flat Tire............... 105
Hazard Warning System ......... 37If Your Car Gets Stuck.......... 112
Jump Starting........................ 110

Shoulder Belt Buckle............. 113

Towing.................................... 111
Warning and Indicator Lights.. 29
Emission Controls........................ 124

Engine
Coolant...................................... 80

Coolant Temperature Gauge... 28
Exhaust Controls................... 125Identification Number............ 12

1
Oil and
Filter.............................. 76
OH Pressure Warning Light..... 30
Specification (Hatchback).... 116
Air Conditioner
Operation.................................. 47

Service...................................... 98

Air Filter.......................................... 86

Air Pressure, Tires......................... 94
Antifreeze.. See "Radiator Coolant" Anti-theft Steering Column Lock System ..................................... 57
Appearance Care........................ 100

Ashtrays......................................... 44

Automatic Seat Belt...................... 10

Automatic Transmission
Driving Technique.................... 66

Fluid........................................... 79

Operation.................................. 64

(cont'd)ProCarManuals.comMain Menu s t

Index (cont'd)

Specification (Sedan)............ 119
Engine Exhaust Gas Warning........ 60
Evaporative Emission Control
System.................................... 125

Exterior Care.................................. 99
Filters

Air.............................................. 86
Engine Oil.................................. 76

Fuel........................................... .86

Fluid..................................... See "Oil"
Foreign Countries, Operation in.... 55
Front Seat
Adjustment................................. 6

Fuel
Filler Door and Cap................... 55
Fitter..........................................86
Gasohol..................................... 54

Gasoline .................................... 54

Gauge........................................ 28

Requirement............................. 54

Fuse
Checking and Replacing .......... 91Specification (Hatchback).... 116
Specification (Sedan)............ 119

Hatch................................................. 5

Hatch/Trunk-open Indicator Light
...................................................31

Hazard Warning System............... 37

Headlights
Flasher...................................... 36
High Beam Indicator................. 29High Beam/Low Beam Switch ...............................................36

Switch...................................... 36

Headlight High Beam Indicator Light
...................................................29

Head Restraints................................ 7
Heating............................................. 50 High Beam
Indicator Light.......................... 29

Switch...................................... 36

Hood Latch..................................... 41
Identification Numbers................ 121
Ignition Keys............................................ 3

Switch....................................... 57

Indicator Lights.............................. 29
Inflation Pressures, Tire................ 94 Instrument Panel............................ 26
Instrument Panel Brightness Control ................................................... 37

Interior Light................................... 37

Interior Trim Care .......................... 99
Keys
Door Locks................................. 3
Hatch/Trunk Lid Lock................ 5

Ignition....................................... 57
Keys............................................ 3
Lap/Shoulder Belts .......................... See "Seat Belts"
Light Bulb Replacement.................... 92
Fuse Replacement................... 90
Operation.................................. 36
Warning and Indicator Lights.. 29
Locks
Anti-theft Steering Column Lock...............................................57
Child Proo f
Door Locks ............. 5

Doors........................................... 3

Fuel Filler Door.......................... 55 Hatch/Trunk Lid......................... 5
Power Doors.............................. 4
Luggage Area Light........................ 38
Luggage Cover................................. 9
Gasoline............................ See "Fuel"
Gas Station Information. back cover

Gauges............................................ 28

Glove Box....................................... 42 Jack.............................................. 106
Jump Starting.............................. 110ProCarManuals.comMain Menu s t