Mazda 1990 MX-5 Instruction manual

CONTENTS
Title Section
General Information GI
Pre-Delivery Inspection and
Scheduled Maintenance Services A
Engine B
Lubrication System D
Cooling System E
Fuel and Emission Control Systems F
Engine Electrical System G
Clutch H
Manual Transmission J
Propeller Shaft L
Front and Rear Axles M
Steering System N
Braking System P
Wheels and Tires Q
Suspension R
Body S
Body Electrical System T
Heater and Air Conditioner
Systems U
Technical Data TD
Special Tools ST
1990
Mazda
MX-5
Workshop
Manual
FORWARD
This workshop manual is intended for use by
service technicians of Authorised Mazda
Dealers to help them service Mazda vehicles. It
can also be useful to owners and operators of
Mazda vehicles in diagnosing some problems
and performing limited repair and maintenance
on Mazda vehicles.
For proper repair and maintenance a
thorough familiarisation with this manual is
important, and it should always be kept in a
handy place for quick and easy reference.
All the contents of this manual, including
drawing and specifications, are the latest
available at the time of printing. As
modifications affecting repair or maintenance
occur, relevant information supplementary to
this volume will be made available at
Authorised Mazda dealers. This manual should
be kept up-to-date.
Mazda Motor Corporation reserves the right
to alter the specifications and contents of this
manual without obligation or advance notice.
Parts Index PI
Mazda Motor Corporation
HIROSHIMA, JAPAN
APPLICATION:
This manual is applicable to vehicles beginning with the
Vehicle Identification Numbers (VIN) shown on the
following page.
©1989 Mazda Motor Corporation
PRINTED IN JAPAN, MAR. ’89
1193-10-89C

VEHICLE IDENTIFICATION NUMBERS (VIN)
JM1 NA351 * LO 100001--
JM1 NA352 * LO 100001-

,--
f
-
GENERAL INFORMATION
IMPORTANT INFORMATION ..................... GI- 2
BASIC ASSUMPTIONS .............•.............. GI- 2
SAFETY RISK ........................................ GI- 2
POSSIBLE LOSS OF WARRANTy ............. GI- 2
WARNING ON LUBRICANTS AND
GREASES •••••••••.•••••••••••...................... GI- 2
HOW TO USE THIS MANUAL .................... GI- 3
PREPARATION .•••.•.....••.••.•••.•••.•••.•••.•••.. GI- 3
REPAIR PROCEDURE ............................. GI- 3
SyMBOLS.•.••••.••••..•••.•..••..••..•...•••••..•••.. GI- 4
NOTES, CAUTIONS, AND WARNINGS ....... GI- 4
FUNDAMENTAL PROCEDURES ................. GI- 4
PROTECTION OF VEHICLE ..................... GI- 4
A WORD ABOUT SAFETy •..•••..•••.•••.•••.••• GI- 5
PREPARATION OF TOOLS AND
MEASURING EQUiPMENT•••.•••••••..••.••..• GI- 5
SPECIAL TOOLS .................................... GI- 5
REMOVAL OF PARTS .•••..•.........•••.•..•..... GI- 5
DiSASSEMBLy ...................................... GI- 5
REASSEMBLy .••.•••.•••...••.•......••.•••.••...•.• GI- 6
ADJUSTMENTS ..................................... GI- 7
RUBBER PARTS
AND TUBING .••••••••••.••.. GI- 7
JACK AND SAFETY STAND POSITIONS .... GI- 8
VEHICLE LIFT (2-SUPPORT TYPE)
POSiTIONS ............................................ GI- 8
TOWiNG••••••••••.••••••••.••••••.••..•••••••••••.•••.• II GI- 9
IDENTIFICATION NUMBER LOCATIONS..... GI- 9
UNITS•••••••••••••••••••••••••• II •••••••••••••••• II ••••••• GI-10
ABBREViATIONS ..................................... GI-10
CAUTION .•••• II' ••••••••••••• II. II' ••••••••••••••••••••• 01-11
INSTALLATION OF MOBILE
TWO-WAY RADIO SYSTEM •••••.••••.••••..•.• 01-11
SERVICE PRECAUTIONS CONCERNING
AIR BAG SYSTEM •.•••..•..••.•••.•••••••.•.•••••
GI-12
BATTERy .............................................. GI-13
POWER CONNECTOR IN
ENGINE COMPARTMENT ...................... GI-13
AUDIO ANTI-THEFT SYSTEM ..••••••••..••••••• GI-13
ELECTRICAL TROUBLESHOOTING TOOLS GI-14
CAUTION WITH ELECTRICAL PARTS••.•••.• 01-15
05UGIX-001
GI

GI
IMPORTANT INFORMATION
IMPORTANT INFORMATION
BASIC ASSUMPTIONS
This workshop manual assumes that you have certain special tools that are necessary for the safe and effi-
cient performance of service operations on Mazda vehicles and that you know how to use them properly.
It also assumes that you are familiar with automobile systems and basic service and repair procedures. You
should not attempt to use this manual unless these assumptions are correct and you understand the conse-
quences described below.
SAFETY RISK
This manual contains certain notes, warnings, and other precautionary information that you should carefully
read and follow to reduce the risk of personal injury to yourself or others and the risk of improper service
that may damage the vehicle or render it unsafe. If there is no such information in regard to any specific
service method, this does not mean there is no possibility that personal safety or vehicle safety will be
jeopardized by the use of incorrect methods or tools.
POSSIBLE LOSS OF WARRANTY
The manufacturer's warranty on Mazda vehicles and engines can be voided
if improper service or repairs
are performed by persons other than those at an Authorized Mazda Dealer.
WARNING ON LUBRICANTS AND GREASES
Avoid all prolonged and repeated contact with mineral oils, especially used oils. Used oils contaminated
during service (e.g., engine sump oils) are more irritating and more likely to cause serious effects, including
skin cancer, in the event of gross and prolonged skin contact.
Wash skin thoroughly after work involving oil.
Protective hand cleaners may be of value provided they can be removed from the skin with water. Do not
use gasoline, paraffin, or other solvents to remove oil from the skin.
Lubricants and greases may be slightly irritating to the eyes.
Repeated or prolonged skin contact should be avoided by wearing protective clothing. Particular care should
be taken with used oils and greases containing lead. Do not allow work clothing to be contaminated with
oil. Dry clean or launder such clothing at regular intervals.
05UGIX-002
GI-2
-
-

HOW TO USE THIS MANUAL
GI
HOW TO USE THIS MANUAL
PREPARATION
PREPARATION points out the needed Special Service Tool (SST) for the service operation that it pre-
ceeds. Gather
all necessary SST before beginning work.
Example:
N TIE-ROD END BOOT AND STEERING GEAR BOOT SST NUMBER
TIE-ROD END BOOT AND STEERING GEAR BOOT
PREPARATION
49 011B B50C
Puller. ball joint
REPAIR PROCEDURE
49 H028 301
Installer. boot
9MUONX·030
SST NAME SST ILLUSTRATION
05UGIX-003
1. Most repair operations begin with an overview illustration. It identifies the components, shows how the
parts fit together, and describes visual parts inspections.
If a damaged or worn part is found, repair or
replace
it as necessary.
2. Expendable parts, tightening torques, and symbols for oil, grease, and sealant are shown in the overview
illustration.
3. Pages related to service procedures are shown under the illustration. Refer to this information when ser-
vicing the related part.
Example:
EXPENDABLE
PARTS
APPLICATION
POINT
OF OIL'Ir_~~~
ETC.
TIGHTENING
TORQUE
SPECIFICATION
*2
(See page GI-4)
L-~~~~~~~ ______________________ ~====~
TIGHTENING
TORQUE UNIT
16. Bearing inner race
Removal ....................................
~e M-22
1W~~~~~tf~W:@@:\~rnfiW~·[:9.Iii~nJQ@m1l1----+- VISUAL
Installation ................................. page M-24 INSPECTION
RELATED
PAGE FOR
SERVICE
17. Spacer INFORMATION
18. Drive pinion
Removal .................................... page
M-21
Inspect splines and teeth for wear or damage
Adjustment
of helght................ page M-22
Ad flqe M-
~----
* 1: The numbers (CD ex.) refer to parts identification and where necessary servicing procedure.
*2: Units are in N·m (m-kg, ft-Ib) unless otherwise specified. 05UGIX-004
GI-3

GI HOW TO USE THIS MANUAL, FUNDAMENTAL PROCEDURES
SYMBOLS
There are six symbols indicating oil, grease, and sealant. These symbols show the points of applying such
materials during service.
Symbol Meaning Kind
.~
• Apply
oil
New engine oil or gear oil as appropriate
~
• Apply brake fluid Only brake fluid
• Apply automatic transmission fluid Only
ATF
i Apply grease Appropriate grease
' .. 1 Apply sealant Appropriate sealant
fj
Apply petroleum jelly Appropriate petroleum jelly
05UGIX-005
Note
• When special oil or grease is needed, this is shown in the illustration.
NOTES, CAUTIONS, AND WARNINGS
As you read through the procedures, you will come across NOTES, CAUTIONS, and WARNINGS. Each
one
is there for a specific purpose. NOTES give you added information that will help you to complete a
particular procedure. CAUTIONS are given to prevent you from making an error that could damage the
vehicle. WARNINGS remind you to be especially careful in those areas where carelessness can cause per-
sonal injury. The following list contains some general WARNINGS you should follow when you work on
a vehicle.
05UGIX-006
GI-4
FUNDAMENTAL PROCEDURES
PROTECTION OF VEHICLE
9MUGIX-036
Always be sure to cover fenders, seats. and floor areas be·
fore starting work.
---

FUNDAMENTAL PROCEDURES
GI
9MUGIX-038
I U"'1 #.,1".1
47UOGX-005
A WORD ABOUT SAFETY
The following precautions must be followed when jacking up
the vehicle.
1. Block the wheels.
2. Use only the specified jacking positions.
3. Support the vehicle with safety stands.
Start the engine only after making certain the engine compart-
ment is clear of tools and people.
PREPARATION OF TOOLS AND MEASURING
EQUIPMENT
Be sure that all necessary tools and measuring equipment are
available before starting any work.
SPECIAL TOOLS
Use special tools when they are required.
REMOVAL OF PARTS
While correcting a problem, try also to determine its cause.
Begin work only after first learning which parts and subassem-
blies must be removed and disassembled for replacement or
repair.
OISASSEMBLY
If the disassembly procedure is complex, requiring many parts
to be disassembled,
all parts should be disassembled in a way
that will not affect their performance or external appearance
and identified
so that reassembly can be performed easily and
effiCiently.
GI-5

GI
GI-6
FUNDAMENTAL PROCEDURES
9MUGIX-042
1. Inspection of parts
When removed, each part should be carefully inspected for
malfunctioning, deformation, damage, and other problems.
2. Arrangement of parts
All disassembled parts should be carefully arranged for re-
assembly.
Be sure to separate or otherwise identify the parts to be
replaced from those that will be reused.
3. Cleaning parts for reuse
All parts to be reused should be carefully and thoroughly
cleaned in the appropriate method.
REASSEMBLY
Standard values, such as torques and certain adjustments,
must be strictly observed
in the reassembly of all parts.
Refer to STANDARD BOLT AND NUT TIGHTENING TORQUE
in Section TO for tightening torques not mentioned in the main
text.
If removed, these parts should be replaced with new ones:
1. Oil seals 2. Gaskets
3. O-rings 4. Lock washers
5. Cotter pins 6. Nylon nuts
Depending on location:
1. Sealant should be applied to gaskets.
2. Oil should be applied to the moving components of parts.
3. Specified oil or grease should be applied at the prescribed
locations (such as oil seals) before reassembly.

FUNDAMENTAL PROCEDURES GI
ADJUSTMENTS
Use suitable gauges and/or testers when making adjustments.
67UOGX-002
RUBBER PARTS AND TUBING
Prevent gasoline or oil from getting on rubber parts or tubing.
,
9MUGIX-005
GI-7

GI JACK AND SAFETY STAND POSITIONS, VEHICLE LIFT (2-SUPPORT TYPE) POSITIONS
JACK AND SAFETY STAND POSITIONS
FRONT
Jack position: Safety stand positions:
At center of crossmember Side sills
REAR
Jack position: Safety stand positions:
At center of differential Side sills
VEHICLE LIFT (2-SUPPORT TYPE) POSITIONS
FRONT
Frame
Side sills
GI-8
REAR
Frame
Side sills
9MUGIX-007
9MUGIX-009
05UGIX-010 .

TOWING, IDENTIFICATION NUMBER LOCATIONS
GI
DOLLY
05UGIX-011
TIEDOWN HOOK-FRONT
TOWING
Proper towing equipment is necessary to prevent damage to
the vehicle during any towing operation.
Laws and regulations applicable to vehicles in tow must al-
ways be observed~
Release the parking brake, place the shift lever in neutral, and
set the ignition switch in the ACC position. As a rule, towed
vehicles should b~ pulled with the driving wheels off the
ground.
WITH MANUAL tRANSMISSION
If the transmissiori, rear axle, and steering system are not
damaged, the vehi:cle may be towed on all four wheels. If any
of these components is damaged, use a towing dolly.
CAUTION
• The power assists for the brakes and steering are
inoperable ~hile the engine is off.
• Do not use tlile tiedown hooks of the vehicle for tow-
ing. These ~ooks are designed ONLV for transport
tiedown. If t~e tiedown hooks are used for towing,
the front or tear skirt and bumper will be damaged.
IDENTIFICATION NUMBER LOCATIONS
VEHICLE IDENTIFICATION NUMBER (VIN) ENGINE MODEL AND NUMBER
INTAKE MANIFOLD
9MUGIX-015
GI-9

GI UNITS, ABBREVIATIONS
UNITS
N·m (m-kg or cm-kg,
ft-Ib or in-Ib).................. Torque
rpm............................... Revolutions per minute
A................................... Ampere(s)
V................................... Volt(s)
0................................... Ohm(s) (resistance)
kPa (kg/cm2, psi).......... Pressure
(usually positive)
mmHg (inHg) ............... Pressure
(usually negative)
W.................................. Watt
liters (US qt, Imp qt) .... Volume
mm (in) ......................... Length
89UOGX-006
GI-10
ABBREVIA liONS
ABDC ................. After bottom dead center
AIC ..................... Air conditioner
ACC .................... Accessories
ATDC.................. After top dead center
BBDC ................. Before bottom dead center
BTDC.................. Before top dead center
DRL .................... Daytime running light
ECU .................... Engine control unit
EGI ..................... Electronic gasoline injection
ElL...................... Electrical load
EX ....................... Exhaust
IC ........................ Integrated circuit
IN ........................ Intake
INT...................... Intermittent
ISC ...................... Idle-speed control
LH ....................... Left hand
LSD..................... Limited slip differential
M ........................ Motor, electric
MIL ..................... Malfunction indicator lamp
MIT ..................... Manual transmission
OFF .................... Switch off
ON ...................... Switch on
PCV .................... Positive crankcase
ventilation
PPF..................... Power plant frame
PRC .................... Pressure regulator control
PIS ...................... Power steering
P/W ..................... Power window
RH ...................... Right hand
SST ..................... Special service tool
TDC .................... Top dead center
VRIS .................... Variable resonance
induction system
05UGIX-012

CAUTION GI
CAUTION
INSTALLATION OF MOBILE TWO-WAY RADIO SYSTEM
If a mobile two-way radio system is installed improperly or if a high-powered type is used, the EGI system
and other systems may be affected.
When the vehicle
is to be equipped with a mobile two-way radio, observe the following precautions:
1. Install the antenna at the farthest point from control units.
2. Install the antenna feeder as far as possible from the control unit harnesses (at least 30 em [11.8 in]).
3. Ensure that the antenna and feeder are properly adjusted.
4. Do not install a high-powered mobile two-way radio system.
FEEDER WIRE CONTROL UNIT HARNESS
fM(
AT LEAST 30 em (11.8 in)
MOBILE TWO-WAY RADIO
ENGINE CONTROL UNIT
CRUISE
FARTH POINT
_.--_ .. _---
05UGIX-013
GI-11

I •
GI
CAUTION
SERVICE PRECAUTIONS CONCERNING AIR BAG SYSTEM
STEERING WHEEL
AIR BAG MODULE
BACKUP BATTERY
05UGIX-014
Before Replacing any Components
Before replacing of any air bag system components, or before disconnecting any connectors of the system,
first disconnect the negative battery cable. Then remove the air bag module from the vehicle even if it has
not failed.
Prohibitation of Component Disassembly and Wiring Harness Repair
The components of the air bag system are not intended to be disassembled for service.
If a component failure is indicated by the diagnostic module, replace the suspected component after verify-
ing the condition of the connections and the wire harness. Do not disassemble any components.
If an open circuit is found by a continuity test, replace the wire harness. Do not attempt to repair the wiring.
Handling of Air Bag Module
1. Do not use an ohmmeter for inspection of the air bag module; it may cause an accidental deployment.
2. When carrying a live air bag module, make sure the trim cover is pointed away from your bodyto prevent
injury in the event of an accidental deployment.
GI-12

CAUTION GI
3. When placing a live air bag module on any surface, always face the trim cover upward. This will reduce
the motion of the module
if it is accidentally deployed.
4. When handling a deployed air bag module, wear gloves and safety glasses because the deployed air
bag module may display deposits of sodium hydroxide, a product of the gas generant combustion.
5. An air bag module must disposed of only by the proper procedure recommended for the specific situa-
tion. (Refer to page T
-160.)
Crash Sensor Installation
1. The angle and direction of the sensor is very important for its proper operation. If a vehicle has been in-
volved in a crash where the its front sheet metal has been damaged, inspect the body structure at the
sensor mounting area for deformation.
If damaged, restore it to its original shape.
2. When installing a crash sensor, be sure to tighten the mounting bolts to the specified torque to ensure
proper grounding. The ground circuit
is made directly through the sensor's mounting plate.
Adjustment of Clock Spring Connector
When the steering wheel is removed or the clock spring connector is replaced, the clockspring connector
must be properly aligned.
Align the clock spring connector
as follows:
(1) Set the front wheels straight ahead.
(2) Turn the clock spring connector clockwise until it stops. Do not force it.
(3) Return it 2.5 turns.
(4) Align (counterclockwise) the mark on the clock spring connector to the outer housing.
(5) Carefully install the steering wheel without disturbing the clockspring connector.
05UGIX-017
05UGIX-018
05UGIX-015
BATTERY
1. The battery is installed in the right rear of the trunk.
2. The battery installed in the MX-5 Miata is unique.
When a replacement battery
is installed, install it with a
Mazda genuine battery replacement kit or equivalent.
(Refer to page
G-10 for replacement.)
POWER CONNECTOR IN ENGINE COMPARTMENT
1. When using externally powered test equippment, connect
it to the special power connector (Blue: i-pin) for battery
voltage.
2. Do not ground the power connector terminal; the Wiper 20A
fuse will be burned.
AUDIO ANTI-THEFT SYSTEM
An audio with an anti-theft function is optionally available.
Before removing the negative battery terminal or disconnect-
ing the audio power source, obtain the code number and deac-
tivate the audio anti-theft system. (Refer to page T -113.)
GI-13

GI
1.4W or 3.4W
05UGIX-019
9MUGIX-020
GROUND
OHMMETER 05UGIX-022
GI-14
CAUTION
ELECTRICAL TROUBLESHOOTING TOOLS
Test Light
The test light, as shown in the figure, uses a 12V bulb. The
two lead wires should be connected to
probes_
The test light is used for simple voltage checks and for check-
ing for short circuits.
Caution
• When checking a control unit, never use a bulb over
3.4W.
Jumper Wire
The jumper wire is used for testing by shorting across switch
terminals and ground connections.
Caution
• Do not connect a jumper wire from the power source
line to a body ground; this may cause burning or
other damage to harnesses or electronic com-
ponents.
Voltmeter
The DC voltmeter is used to measure circuit voltage. A volt-
meter with a range of 15V or more is used by connecting the
positive
(+) probe (red lead wire) to the point where voltage
is to be measured and the negative (-) probe (black lead
wire) to a body ground.
Diagnosis Connector
Insert the probe into the service hole when connecting a jum-
per wire to the diagnosis connector.
Caution
• Do not insert the jumper wire probe into the diag-
nosis connector terminal, which may damage the
terminal.
Ohmmeter
The ohmmeter is used to measure the resistance between two
points
in a circuit, and to check for continuity and short circuits.
Caution
• Do not attempt to connect the ohmmeterto any cir-
cuit to which voltage is applied; this may burn or
otherwise damage the ohmmeter.

IF
-'$
I'-
~
~
b 05UGIX-025
05UGIX-026
,-
05UGIX-027
I. ,
CAUTION
CAUTION WITH ELECTRICAL PARTS
Battery Cable .
GI
Before disconnecting connectors or removing electrical parts,
disconnect the negative battery cable.
Connectors
Disconnecting connectors
Never pull on the wire harness when disconnecting con-
nectors.
Connectors can be disconnected by pressing or pulling the
lock lever as shown,
Locking connectors
When locking connectors, listen for a click that will indicate
they are securely locked.
Inspection
1. When a tester is used to check for continuity or to measure
voltage, insert the tester probe from the wire harness side.
GI-15

GI
9MUGIX-028
05UGIX-029
GI-16
CAUTION
2. Check the terminals of waterproof connectors from the con-
nector side,
as they cannot be accessed from the wire har-
ness side.
Caution
• Use fine wire to prevent damage to the terminal.
• Do not damage the terminal when inserting the
tester lead.
Terminals
Inspection
Pull lightly on individual wires to check that they are secured
in the terminal.
Replacement of terminals
Use the appropriate tools to remove the terminal as shown.
When installing the terminal, be sure to insert
it until it locks
securely.
<Female>
Insert a thin piece of metal from the terminal side of the con-
nector, and then, with the terminal locking tab pressed down,
pull the terminal out from the connector.
<Male>
Same as the female type.
Sensors, Switches, and Relays
Handle sensors, switches, and relays carefully. Do not drop
them or strike them against other objects.

BfR
BRIY
05UGIX-030
PULLER
t
~FUSE_,,--=--,--_
9MUGIX-032
CAUTION
Wire Harness
Wiring color codes
GI
Two-color wires are indicated by a two-color code symbol.
The first letter indicates the base color of the wire and the sec-
ond the color of the stripe.
CODE
B
BR
G
GY
L
LB
LG
Fuse
Replacement
COLOR
Black
Brown
Green
Gray
Blue
Light Blue
Light Green
CODE
COLOR
0 Orange
P Pink
R Red
V Violet
W White
Y Yellow
--
1. When replacing a fuse, be sure to replace it with one of the
specified capacity.
If a fuse again fails after it has been replaced, the circuit
probably has a short and the wiring should be checked.
2. Be sure the negative battery terminal is disconnected be-
fore replacing a main fuse (80A).
3. When replacing a pullout fuse, use the fuse puller supplied
in the fuse box cover.
GI-17

PRE-DELIVERY INSPECTION
AND
SCHEDULED MAINTENANCE
SERVICES
PRE-DELIVERY INSPECTION ..................... A- 2
PRE-DELIVERY INSPECTION TABLE .......... A- 2
SCHEDULED MAINTENANCE SERViCES ..... A- 3
SCHEDULE 1
(NORMAL DRIVING CONDITIONS) •••...••... A- 3
SCHEDULE 2
(UNIQUE DRIVING CONDITIONS) •••....•.... A- 6
05UOAX-001
A