1997 MAZDA MIATA Camshaft

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.

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.

wheel puller. Pry out seal.
Installation
1. Apply light oil coat to seal lip. Using a hammer and seal installer, tap seal into oil pump body until it is
flush with edge of pump body. DO NOT bottom seal in pump body. Align keyway slots, and install
crankshaft sprocket and Woodruff key with tapered side toward oil pump body. Install crankshaft
sprocket bolt.
2. Using Crankshaft Lock Tool (49-D011-102), lock crankshaft sprocket into position. Tighten lock bolt to
specification. See TORQUE SPECIFICATIONS
.
3. Install timing belt. See TIMING BELT
under REMOVAL & INSTALLATION. Install timing belt
covers, pulleys and drive belts. Reconnect negative battery cable and ensure timing is correct.
TIMING BELT
Removal (Miata)
1. Disconnect negative battery cable. Drain cooling system. Remove radiator hose and by-pass hoses from
thermostat housing. Remove air cleaner intake duct assembly from between throttle body and air cleaner
filter housing.
2. Remove drive belts and water pump pulley. Align crankshaft pulley timing mark with cylinder No. 1 at
TDC of compression stroke. Hold crankshaft pulley stationary. Remove crankshaft pulley bolts and
pulley. Remove crankshaft pulley hub bolt and hub.
3. Remove cylinder head cover. Remove upper, center and lower timing belt cover. If timing belt is to be
reused, mark timing belt rotation direction. Ensure timing marks on camshaft sprockets are aligned. See
Fig. 8
. Loosen timing belt tensioner lock bolt, and move tensioner away from belt with spring fully
expanded. Remove timing belt.
Removal (Protege)
1. Disconnect negative battery cable. Raise and support vehicle. Remove right front wheel. Remove right
side cover and undercover.
2. Remove drive belts and water pump pulley. Align crankshaft pulley timing mark with cylinder No. 1 at
TDC of compression stroke. Hold crankshaft stationary. Remove crankshaft pulley bolts and pulley.
Remove crankshaft pulley hub bolt and hub.
3. Remove cylinder head cover. Remove upper, center and lower timing belt cover. If timing belt is to be
reused, mark timing belt rotation direction. Ensure timing marks on camshaft sprockets are aligned. See
Fig. 8
. Loosen timing belt tensioner lock bolt, and move tensioner away from belt with spring fully
expanded. Remove timin
g belt. NOTE: For 1997-98 vehicles, the manufacturer recommends the belt be replaced at
60,000 mile intervals for vehicles sold outside of California and Massachusetts.
For vehicles sold in California and Massachusetts, inspect timing belt at 60,000
and 90,000 miles, and replace timing belt at 105,000 miles.

1997 Mazda MX-5 Miata
1997-98 ENGINES 1.8L 4-Cylinder
Microsoft
Sunday, July 05, 2009 1:55:15 PMPage 12 © 2005 Mitchell Repair Information Company, LLC.

Inspection (All Models)
Check timing belt for cracks, peeling, abrasion or other damage. Check tensioner bearing for looseness or
roughness of rotation. Inspect tensioner spring for stretching. Replace parts as necessary.
Installation (All Models)
1. Position notch on crankshaft sprocket to 12 o'clock position (aligned with mark on oil pump). Align
timing marks on camshaft sprockets. See Fig. 8
. Ensure crankshaft timing mark is at TDC. Install belt
around crankshaft sprocket, then working in a counterclockwise direction, route belt around camshaft
sprockets.
2. Loosen timing belt tensioner lock bolt and allow spring to apply tension on belt. Snug tensioner lock bolt.
Rotate crankshaft 2 complete turns in direction of normal engine rotation. Ensure timing marks align. If
timing marks are not aligned, remove belt, realign all timing marks, and repeat installation procedure.
3. Check timing belt deflection with 22 lbs. (10 kg) of pressure applied to belt. See Fig. 9
. Ensure timing
belt deflection is within specification. See TIMING BELT DEFLECTION
.
TIMING BELT DEFLECTION
Application(1) Deflection In. (mm)
Miata & Protege.35-.45 (9.0-11.5)
(1)Deflection measurement is with 22 lbs. (10 kg) of pressure applied to timing belt. See Fig. 9 .

1997 Mazda MX-5 Miata
1997-98 ENGINES 1.8L 4-Cylinder
Microsoft
Sunday, July 05, 2009 1:55:15 PMPage 13 © 2005 Mitchell Repair Information Company, LLC.

Fig. 8: Aligning Camshaft Timing Marks
Courtesy of MAZDA MOTORS CORP.

1997 Mazda MX-5 Miata
1997-98 ENGINES 1.8L 4-Cylinder
Microsoft
Sunday, July 05, 2009 1:55:15 PMPage 14 © 2005 Mitchell Repair Information Company, LLC.

Fig. 9: Measuring Timing Belt Deflection
Courtesy of MAZDA MOTORS CORP.
HYDRAULIC LASH ADJUSTER (HLA)
Removal
Disconnect negative battery cable. Remove camshaft. See CAMSHAFT . Mark location of each HLA for
reassembly reference. Remove HLA from cylinder head.
Inspection
Place HLA in palm of hand. Attempt to compress HLA plunger with thumb. If plunger compresses, replace
HLA.
NOTE: If hydraulic lash adjusters are persistently noisy, check with manufacturer for
availability of modified adjusters.

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

Installation
Insert HLA in original location. To complete installation, reverse removal procedure. Tighten camshaft bearing
caps evenly in sequence to specification. See Fig. 10
or Fig. 11 . See TORQUE SPECIFICATIONS .
CAMSHAFT
Removal
Remove cylinder head cover. Remove timing belt. See TIMING BELT. Remove distributor/camshaft position
sensor. Reference mark camshafts, caps and sprockets, and remove sprockets. Loosen camshaft bearing cap
bolts evenly in 5-6 steps, in sequence. See Fig. 10
or Fig. 11 . Remove camshafts.
Inspection
Check camshaft end play. Check camshaft journal diameters and bearing clearances. Check camshaft lobes for
wear. See CAMSHAFT
under ENGINE SPECIFICATIONS. If any measurement is not within specification,
replace camshaft and/or cylinder head.
Installation
To install, reverse removal procedure. On both camshafts, apply small amount of silicone sealant to contact area
of cylinder head/camshaft seal cover cap. Tighten camshaft bearing cap bolts evenly in sequence to
specification. See Fig. 10
or Fig. 11 . See TORQUE SPECIFICATIONS. NOTE: On Miata, exhaust camshaft has a slot for camshaft position sensor drive. On
Protege, exhaust camshaft has a slot for distributor drive. On all models, match
mark camshafts and sprockets for installation reference.

1997 Mazda MX-5 Miata
1997-98 ENGINES 1.8L 4-Cylinder
Microsoft
Sunday, July 05, 2009 1:55:15 PMPage 16 © 2005 Mitchell Repair Information Company, LLC.

Fig. 10: Camshaft Bearing Cap Bolt Removal & Installation Sequence (Miata) Removal
Courtesy of MAZDA MOTORS CORP.

1997 Mazda MX-5 Miata
1997-98 ENGINES 1.8L 4-Cylinder
Microsoft
Sunday, July 05, 2009 1:55:15 PMPage 17 © 2005 Mitchell Repair Information Company, LLC.