Engine Controls - Remove/install/overhaul: Other Mazda MX-5 NA

DISTRIBUTOR

Note. Miata, Navajo and RX7 are equipped with distributorless ignition system.

Refer to appropriate illustration when removing, overhauling or installing distributor. (Scheme 11)- (Scheme 17).

Scheme 11

Scheme 12

Scheme 13

Scheme 14

Scheme 15

Scheme 16

Scheme 17

FUEL SYSTEM

Except Navajo

1. Start engine. On B2200 PFI, B2600i, Miata,MX-6, RX7, 626 and 929, disconnect fuel pump relay or circuit opening relay. See the «FUEL PUMP/CIRCUIT OPENING RELAY LOCATION»(ref-18285-S36682137932000123000000) table.
2. On MPV 3.0L, disconnect airflow sensor connector. On all other models, disconnect fuel pump connector near fuel tank (on MX-3, Protege and 323, fuel pump connector is accessible from under rear seat cushion).
3. On all models, allow engine to run until it stalls. Turn ignition off. Reconnect electrical connector.

FUEL PUMP/CIRCUIT OPENING RELAY LOCATION

Navajo

1. Disconnect negative battery cable. Remove snow/ice shield. Remove air intake tube between air cleaner and throttle body. Remove fuel filler cap to release fuel tank pressure. Connect Fuel Pressure Gauge (49-UN01-010) to fuel pressure relief valve (Schrader valve) on fuel supply manifold, near fuel pressure regulator. see scheme 25
2. As an alternate method, disconnect inertia switch connector behind instrument panel, under radio. Start engine and operate until it stalls.

FUEL LINE CONNECTORS (NAVAJO)

Note. Although push-connect fittings and spring lock couplers are similar in function, different procedures and tools are used to disconnect and connect these connectors. (Scheme 18)and (Scheme 19).

Disconnect (Push-Connect Fitting)

1. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(ref-18285-S39855759662000123000000). Remove locking (safety) clip (if equipped).
2. Position Push-Connect Fitting Releaser (49-UN01-053 for 5/16" line; 49-UN01-054 for 3/8" line) over fuel line. (Scheme 18) Slide releaser into fitting. Pull fuel lines apart.

Connect

Press fuel lines together until a click is heard. Attempt to pull lines apart to ensure coupler is fully engaged. Install locking clip (if equipped).

Scheme 18

Disconnect (Spring Lock Coupler)

1. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(ref-18285-S39855759662000123000000). Remove locking (safety) clip (if equipped). Place Spring Lock Coupler Releaser (49-UN01-051 for 3/8" line; 49-UN01-052 for 1/2" line) over fuel line coupler. (Scheme 19)
2. Push spring lock coupler releaser to release female fitting from garter spring. Pull spring lock coupler apart. Remove releaser.

Connect (Spring Lock Coupler)

1. Check for damaged garter spring. If garter spring is damaged, remove using small hooked wire and replace spring. Wipe end of lines using clean cloth. Place new "O" rings onto tube. Lubricate ends of lines with clean refrigerant oil.
2. Push fitting together using a slight twisting motion. Ensure garter spring is over flared end of female fitting. Attempt to pull lines apart to ensure coupler is fully engaged. Install locking clip (if equipped).

Scheme 19

FUEL SYSTEM PRIMING

1. On B2200 PFI, B2600i, and MPV, connect jumper wire between terminals of Yellow 2-pin connector. See «FUEL PUMP TEST CONNECTOR LOCATION»(ref-18285-S13649259842000123000000) table.
2. On all others, connect jumper wire between GND and F/P terminals of data link connector. (Scheme 20) On all models, turn ignition on for about 10 seconds and then off. Disconnect jumper wire.

Without starting engine, turn ignition on and off 5-10 times.

FUEL PUMP TEST CONNECTOR LOCATION

Scheme 20

Adjusting Float Level

With air horn upside-down and gasket removed, allow float to hang by its weight. Measure distance between top of float and air horn gasket surface. (Scheme 21) If distance is not.42-.46" (10.7-11.7 mm) on A/T models or.46-.50" (11.7-12.7 mm) on M/T models, bend float seat as necessary.

Adjusting Float Drop

With air horn upright and gasket removed, allow float to hang by its weight. Measure between bottom of float and air horn gasket surface. (Scheme 22) If distance is not 1.81-1.85" (46.0-47.0 mm), bend float stop as necessary. (Scheme 21)

Scheme 21

Scheme 22

Adjusting Choke Pull-Off Diaphragm

Apply about 16 in. Hg vacuum to choke pull-off diaphragm. Lightly push choke plate toward closed position. Measure clearance between top of choke plate and air horn. (Scheme 23) If clearance is not.067-.085" (1.70-2.16 mm), bend choke lever until clearance is within specification.

Adjusting Fast Idle Cam (Throttle Opening Angle)

Set fast idle cam on second highest position. Measure between primary throttle valve and throttle bore. (Scheme 24) If clearance is not.033-.041" (0.84-1.04 mm), turn fast idle adjusting screw as necessary.

Scheme 23

Scheme 24

Adjusting Fast Idle Cam (Choke Valve Angle)

Set fast idle cam on second highest position. Measure clearance between top of choke plate and air horn. (Scheme 25) If clearance is not.024-.045" (0.60-1.14 mm), bend starting arm. If large adjustment is required, bend choke rod.

Adjusting Choke Unloader

Fully open primary throttle valve. Measure clearance between top of choke plate and air horn. (Scheme 26) If clearance is not.110-.143" (2.80-3.62 mm), bend tab as necessary.

Scheme 25

Scheme 26

Adjusting Secondary Throttle Valve

Secondary throttle valve should start to open when primary throttle valve opens 50-54 degrees and should be fully open when primary throttle valve is fully open. Measure clearance between primary throttle valve and throttle bore when secondary throttle valve starts to open. (Scheme 27) If clearance is not.289-.325" (7.35-8.25 mm), bend tab as necessary.

Adjusting Accelerator Cable

Check accelerator cable deflection (free play) at carburetor. If deflection is not .039-.118" (1.0-3.0 mm), turn cable adjusting nuts as needed. Fully depress accelerator pedal. If primary throttle valve does not fully open, turn accelerator stop bolt (above accelerator pedal) as needed to obtain full valve opening.

Scheme 27

Scheme 28

FUEL PUMP

FUEL PRESSURE REGULATOR

FUEL RAILS & INJECTORS

THROTTLE BODY