1997 MAZDA MX-5 Engine control

MOTORS
MOTORS
SENDING UNITS & SENSORS
SENDING UNITS & SENSORS
Key Interlock UnitBehind left side of dash. See Fig. 2 .
SAS UnitBehind center of dash. See Fig. 2 .
Transmission Control Module (TCM)Under left side of dash, near fuse block. See Fig. 2 .
ComponentComponent Location
Blower MotorUnder right side of dash. See Fig. 2 .
Condenser Fan MotorIn front of engine compartment.
Cooling Fan MotorIn front of engine compartment.
Cruise Control ActuatorOn left side of engine compartment.
Fuel PumpIn fuel tank.
Power Antenna MotorIn right front of trunk.
Retractable Headlamp ActuatorsBehind respective headlamp.
Shift Lock ActuatorUnder center console, on base of gear selector.
Windshield Washer MotorOn bottom of washer fluid reservoir.
Windshield Wiper MotorOn right side of firewall.
ComponentComponent Location
ABS Wheel Speed Sensor (Left Front)On back of left front wheel spindle assembly. See Fig. 1 .
ABS Wheel Speed Sensor (Left Rear)On back of left rear wheel hub assembly. See Fig. 3 .
ABS Wheel Speed Sensor (Right Front)On back of right front wheel spindle assembly. See Fig. 1 .
ABS Wheel Speed Sensor (Right Rear)On back of right rear wheel hub assembly. See Fig. 3 .
Brake Fluid Level SensorIn brake fluid reservoir. See Fig. 1 .
Camshaft Position SensorIn center rear of engine compartment. See Fig. 1 .
Crankshaft Position SensorOn front of engine.
EGR Boost SensorOn right side of engine compartment.
EGR Valve Position SensorOn right side center, rear of engine compartment.
EGR Valve Position SensorOn right side center, rear of engine compartment. See Fig. 1 .
Engine Coolant Temperature SensorOn rear of engine. See Fig. 1 .
Fuel Gauge Sender UnitIn fuel tank.
Heated Oxygen Sensor (Front)In rear of engine compartment. See Fig. 1 .
Heated Oxygen Sensor (Rear)On underside of vehicle, on exhaust pipe.
Input/Turbine Speed SensorOn left side of transmission.
Mass Air Flow SensorOn top of air filter housing. See Fig. 1 .
Throttle Position (TP) SensorOn side of throttle body. See Fig. 1 .
Transmission Fluid Temperature SensorOn left side of transmission.

1997 Mazda MX-5 Miata
1997 MAZDA MX-5 Miata
Microsoft
Sunday, July 05, 2009 1:54:00 PMPage 2 © 2005 Mitchell Repair Information Company, LLC.

SOLENOIDS & SOLENOID VALVES
SOLENOIDS & SOLENOID VALVES
SWITCHES
SWITCHES
MISCELLANEOUS
MISCELLANEOUS
Vehicle Speed Sensor (VSS)On speedometer assembly.
Water Temperature Sender UnitOn center of engine. See Fig. 1 .
Washer Fluid Level SensorOn washer fluid reservoir. See Fig. 1 .
ComponentComponent Location
AT Interlock SolenoidIn steering column, near ignition switch. See Fig. 2 .
EC-AT Solenoid ValveOn left side of transmission.
EGR Solenoid Valve (Vacuum)On right side of engine compartment. See Fig. 1 .
EGR Solenoid Valve (Vent)On right side of engine compartment. See Fig. 1 .
Fourth Gear Solenoid ValveOn left side of transmission.
Idle Air Control ValveOn right side, front of engine compartment. See Fig. 1 .
PRC Solenoid ValveOn right side, front of engine. See Fig. 1 .
Purge Solenoid ValveOn right strut tower. See Fig. 1 .
ComponentComponent Location
Back-Up Lamp Switch (M/T)On right side of transmission. See Fig. 1 .
Brake SwitchOn bracket, above brake pedal. See Fig. 2 .
Buckle SwitchOn driver side seat belt buckle. See Fig. 3 .
Clutch Switch (M/T)On bracket, above clutch pedal. See Fig. 2 .
Hold SwitchUnder right side of center console.
Key Reminder SwitchIn steering column, near ignition switch.
Neutral Switch (M/T)On right side of transmission. See Fig. 1 .
Oil Pressure SwitchOn right side of engine. See Fig. 1 .
"P" Range SwitchUnder center console, on base of gear selector.
Parking Brake SwitchOn base of parking brake lever. See Fig. 4 .
Power Steering Pressure SwitchOn power steering pump assembly.
Refrigerant Pressure SwitchIn front of engine compartment, near radiator support. See Fig. 1 .
Starter Interlock Switch (M/T)On bracket, above clutch pedal. See Fig. 2 .
ThermoswitchUnder right side of dash.
Transmission Range SwitchOn left side of transmission.
ComponentComponent Location

1997 Mazda MX-5 Miata
1997 MAZDA MX-5 Miata
Microsoft
Sunday, July 05, 2009 1:54:00 PMPage 3 © 2005 Mitchell Repair Information Company, LLC.

Fig. 2: Removing & Installing Drive Train Components (Miata)
Courtesy of MAZDA MOTORS CORP.
3. Remove all cooling system hoses and A/T oil cooler hoses at radiator (if equipped). Remove radiator and
cooling fans as an assembly. Remove all drive belts. DO NOT disconnect power steering hoses or A/C
compressor hoses. Unbolt power steering pump and A/C compressor from engine, and wire aside.
4. Remove air cleaner assembly. See Fig. 3
. Remove throttle cable. Note locations and disconnect all
necessary electrical connectors, ground wires, vacuum hoses, fuel hoses, coolant hoses and control cables
for engine removal. Plug all fuel hoses to prevent leakage. Remove engine mount nuts and remove
en
gine.

1997 Mazda MX-5 Miata
1997-98 ENGINES 1.8L 4-Cylinder
Microsoft
Sunday, July 05, 2009 1:55:15 PMPage 4 © 2005 Mitchell Repair Information Company, LLC.

Fig. 5: Removing Engine Components (Protege)
Courtesy of MAZDA MOTORS CORP.
2. Lower vehicle. Remove air cleaner assembly. Remove battery/carrier assembly. Remove throttle cable
and air intake duct across radiator (if equipped).
3. Remove all drive belts. DO NOT disconnect power steering hoses or A/C compressor hoses. Unbolt
power steering pump and A/C compressor from engine, and wire aside.
4. Note locations and disconnect all necessary electrical connectors, ground wires, vacuum hoses, fuel
hoses, coolant hoses and control cables for engine removal.
5. Plug all fuel hoses to avoid leakage. Attach engine support bar or engine hoist to secure engine. Raise
vehicle. Disconnect exhaust manifold down pipe and exhaust brackets from engine. On A/T models,
remove shift control cable.
6. On M/T models, remove shift control linkage and extension bar. Remove clutch release cylinder and fluid
line bracket from transaxle housing, leaving fluid line connected to cylinder. Secure cylinder away from
transaxle.
7. On all models, remove transmission wiring harness connectors and speedometer cable. Remove axle shaft
nuts from hubs. Disconnect stabilizer bar from lower control arms. Separate lower ball joints and steering
tie-rod ends from steering knuckles.
8. Pry axle shafts out of transaxle. Remove and discard circlip from axle shafts. For further information on
axle shafts, see appropriate article in DRIVE AXLES.
9. Remove transaxle mount nuts from crossmember and loosen crossmember bolts. See Fig. 6
. Lower
vehicle and attach engine hoist for engine removal. Remove engine front mount and transaxle top mount
from inner fender panels. Remove transaxle crossmember. Remove engine and transaxle assembly from
top of vehicle.
10. To install, reverse removal procedure. Tighten bolts and nuts to specifications. See TORQUE
SPECIFICATIONS . Fill all fluids to correct level. Prime fuel system before attempting to start engine.
See FUEL PRESSURE RELEASE & PRIMING
. Bleed cooling system. See COOLING SYSTEM
BLEEDING.

1997 Mazda MX-5 Miata
1997-98 ENGINES 1.8L 4-Cylinder
Microsoft
Sunday, July 05, 2009 1:55:15 PMPage 8 © 2005 Mitchell Repair Information Company, LLC.

2. Disconnect throttle cable. Remove fuel lines from fuel rail and pressure regulator. Remove throttle body
intake duct housing and throttle body. Remove by-pass air control valve and solenoid valves. Remove
upper intake manifold (if equipped).
3. Remove intake manifold support bracket from underneath manifold. Disconnect injector harness
connectors, and remove injectors/fuel rail assembly. Remove intake manifold and gasket.
Installation
1. Ensure all gasket surfaces are clean and flat. Using NEW gasket, install intake manifold to cylinder head.
Tighten manifold bolts/nuts evenly to specification, starting from center bolt and alternating outward. See
TORQUE SPECIFICATIONS
. Install support bracket underneath intake manifold.
2. Install gasket and upper intake manifold (if equipped). Tighten bolts/nuts evenly to specification,
alternating from top to bottom. See TORQUE SPECIFICATIONS
.
3. To complete installation, reverse removal procedure. Ensure throttle cable has .04-.12" (1-3 mm) free
play. Ensure injectors twist freely and are not cocked in insulator "O" rings. Refill engine with coolant.
EXHAUST MANIFOLD
Removal & Installation
1. Remove air cleaner intake duct from top of radiator/fan assembly (if equipped). Disconnect oxygen
sensor. Remove heat shields. Disconnect down pipe from exhaust manifold. Remove exhaust manifold.
2. To install, reverse removal procedure. Ensure all mating surfaces are clean and flat. Install NEW exhaust
manifold gasket to cylinder head. Tighten manifold bolts evenly to specification, starting from center bolt
and alternating outward. See TORQUE SPECIFICATIONS
.
CYLINDER HEAD
Removal
1. Release residual pressure from fuel system. See FUEL PRESSURE RELEASE & PRIMING . Drain
engine coolant. Note locations and disconnect all necessary electrical connectors, ground wires, vacuum
hoses, fuel hoses, coolant hoses and control cables for cylinder head removal. Plug all fuel hoses to avoid
leakage.
2. Remove spark plug wires from spark plugs. Remove all drive belts. Remove water pump pulley. Remove
timing belt. See TIMING BELT
. Remove camshaft/rocker cover.
3. Remove front exhaust pipe. Remove intake manifold support bracket. Loosen all cylinder head bolts
evenly, in 3 steps, in reverse of tightening sequence. See Fig. 7
. Remove bolts and cylinder head
assembly.
Inspection
Carefully clean carbon and gasket material from all mating surfaces. Clean threads of cylinder head bolts. Use a
tap to clean threads in engine block. Check cylinder head for warpage. Resurface or replace head if it is not
within specification. Check valve train components. Replace or resurface components if they are not within

1997 Mazda MX-5 Miata
1997-98 ENGINES 1.8L 4-Cylinder
Microsoft
Sunday, July 05, 2009 1:55:15 PMPage 10 © 2005 Mitchell Repair Information Company, LLC.

OIL PUMP
Removal & Disassembly
1. Disconnect negative battery cable. Remove dipstick, tube and "O" ring. Drain engine oil and coolant.
Remove drive belts, crankshaft and water pump pulleys. Remove generator, A/C compressor and
mounting bracket. Without disconnecting A/C hoses, secure A/C compressor away from engine. Remove
timing belt and related components. See TIMING BELT
under REMOVAL & INSTALLATION.
2. Hold crankshaft sprocket in place and remove crankshaft sprocket bolt. Remove crankshaft sprocket
using steering wheel puller. Leave crankshaft Woodruff key in place.
3. Remove oil pan and oil pump pick-up tube. See OIL PAN
under REMOVAL & INSTALLATION.
Remove oil pump housing assembly. Using a screwdriver protected with a rag, drive oil seal out from
inside of oil pump housing assembly.
4. Remove pump cover screws (use a manual impact screwdriver, if necessary). See Fig. 22
. Remove pump
cover. Note location of alignment marks on inner and outer rotors. Remove inner and outer rotors. To
remove pressure relief valve, remove spring seat, pressure spring and control plunger.
Inspection
Replace pressure relief valve spring if length is not as specified. See OIL PUMP SPECIFICATIONS. Ensure
plunger slides freely in bore. Replace oil pump housing assembly if clearances are not as specified. See OIL
PUMP SPECIFICATIONS .
Reassembly & Installation
1. Apply oil to friction surfaces. Install inner and outer rotors with marks aligned. See Fig. 23 . Install
pressure relief valve components. Apply oil to lip of NEW oil seal. Press oil seal into bore until even with
face of oil pump housing assembly.
2. Install pump cover. Tighten screws to 53-78 INCH lbs. (6-9 N.m). To complete installation, reverse
removal procedure. Tighten bolts to specification. See TORQUE SPECIFICATIONS
.
OIL PUMP SPECIFICATIONS
ApplicationW/O Filter Qts. (L)W/Filter Qts. (L)
Miata & Protege3.8 (3.6)4.0 (3.8)
ApplicationMaximum Clearance In. (mm)
Maximum Rotor Tip Clearance (1) .0079 (.20)
Maximum Rotor-To-Pump Body Clearance (2) .0079 (.20)
Maximum Rotor Side Clearance (3) .0055 (.14)
Pressure Relief Spring Free Length1.809 (45.94)
(1)See Fig. 23 .
(2)Insert feeler gauge between outer rotor and pump body.
Place straightedge across pump body and check clearance between straightedge and both rotors.

1997 Mazda MX-5 Miata
1997-98 ENGINES 1.8L 4-Cylinder
Microsoft
Sunday, July 05, 2009 1:55:15 PMPage 33 © 2005 Mitchell Repair Information Company, LLC.

Check for damage, excessive wear and signs of bearing seizure. Inspect steering knuckle and hub for cracks,
scoring and rust. Check for damaged dust cover and poor fit with steering knuckle. Replace components as
necessary.
Installation
To install, reverse removal procedure. Adjust wheel bearing preload. See WHEEL BEARING
ADJUSTMENT under ADJUSTMENTS. Stake axle nut.
LOWER CONTROL ARM & BALL JOINT
Removal
1. Raise and support vehicle. Remove wheel assembly. Remove engine splash shield (if equipped). Separate
tie rod end from steering knuckle (as necessary). Remove stabilizer bar from lower control arm.
2. Remove shock lower mounting bolt and separate lower shock from lower control arm. Remove lower
control arm ball joint cotter pin and nut. Separate lower control arm ball joint stud from knuckle using
Puller (49 T028 3A0). Remove lower control arm pivot bolts and remove lower control arm.
Inspection
Check lower control arm for damage or cracks. Check bushings for deterioration and excessive wear. Check
ball joint for excessive wear. Examine dust boot for damage. Replace components as necessary.
Bushing Replacement
Cut or press old bushing from control arm. Coat NEW bushing with paraffin-based oil. Press new bushing into
control arm.
Installation (All Models)
To install, reverse removal procedure. Tighten lower control arm-to-frame bolts to specification with vehicle
resting on ground and suspension unloaded. See TORQUE SPECIFICATIONS
.
UPPER CONTROL ARM & BALL JOINT
Removal
Raise and support vehicle. Remove wheel assembly. Remove engine splash shield. Remove wheel speed sensor
harness band. Remove shock lower mounting bolt, and separate lower shock from lower control arm. Remove
upper control arm ball joint cotter pin and nut. Separate upper control arm ball joint stud from knuckle using
Puller (49-0118-850C). Remove upper control arm pivot bolts and remove upper control arm.
Inspection
Check upper control arm for damage or cracks. Check bushings for deterioration and excessive wear. Check
ball joint for excessive wear. Examine dust boot for damage. Replace components as necessary.

1997 Mazda MX-5 Miata
1997-2000 SUSPENSION Front - Miata
Microsoft
Sunday, July 05, 2009 1:38:08 PMPage 3 © 2005 Mitchell Repair Information Company, LLC.

Bushing Replacement
Cut or press old bushing from control arm. Coat new bushing with paraffin-based oil. Press new bushing into
control arm.
Installation (All Models)
To install, reverse removal procedure. Tighten upper control arm pivot bolts to specification with vehicle
resting on ground and suspension unloaded. See TORQUE SPECIFICATIONS
.
SHOCK ASSEMBLY
Removal (1997)
Raise and support vehicle. Remove wheel assembly. Remove engine splash shield. Remove wheel speed sensor
harness band. Remove stabilizer link bolt. Remove upper control arm ball joint cotter pin and nut. Separate
upper control arm ball joint stud from knuckle using Puller (49-0118-850C). Loosen lower control arm pivot
bolts. Remove shock upper mount nuts and lower bolt. Move lower control arm just enough to remove shock
assembly. DO NOT damage brake line.
Removal (1999 & 2000)
Raise and support vehicle. Remove wheel assembly. Remove engine splash shield. Remove wheel speed sensor.
Remove stabilizer link bolt. Separate lower control arm ball joint stud from knuckle using Puller (49-T028-
3A0). Loosen lower control arm pivot bolts. Inside engine compartment, on 1999 models, remove strut bar. See
FRONT STRUT BAR (1999)
. On 2000 models, remove shock upper mount nuts. On all models, under car,
remove lower bolt. Move lower control arm just enough to remove shock assembly. DO NOT damage brake
line.
Disassembly
Clamp upper shock mount in vise. Loosen piston lock nut 2 turns only. Compress coil spring using coil spring
compressor. Remove piston lock nut. Slowly release compressor tension. Remove components. Remove coil
spring. Remove shock from vise.
Inspection
Check shock tube for damage, oil leakage and abnormal noise. Check rubber components for deterioration or
damage. Inspect coil spring for signs of fatigue or damage. Replace components as necessary.
Reassembly (1997)
Clamp shock in vise. Install coil spring and components in reverse order of disassembly. Ensure coil spring is
well seated in upper and lower spring seats. See Fig. 2
. Tighten piston rod nut. See TORQUE
SPECIFICATIONS .

1997 Mazda MX-5 Miata
1997-2000 SUSPENSION Front - Miata
Microsoft
Sunday, July 05, 2009 1:38:08 PMPage 4 © 2005 Mitchell Repair Information Company, LLC.