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Engine Controls - Adjustments Mitsubishi Eclipse I

Adjustments 3 illustrations ~1515 words

INTRODUCTION

Note. Introduction information not applicable.

ENGINE MECHANICAL

Before performing any on-vehicle adjustments to fuel or ignition system, ensure engine mechanical condition is okay.

CHECKING HYDRAULIC VALVE LIFTERS

  1. Warm engine to normal operating temperature. Remove valve cover. Position No. 1 cylinder at TDC on compression stroke. Check intake rockers on No. 1 and 2 cylinders. Check exhaust rockers on No. 1 and 3 cylinders.
  2. Push downward on end of rocker arm above lash adjuster. Rotate crankshaft 360 degrees and check intake rockers on No. 3 and 4 cylinders. Check exhaust rockers on No. 2 and 4 cylinders. If lash adjuster is normal, it will feel solid.
  3. If lash adjuster moves downward easily when pushed, replace adjuster. If lash adjuster feels soft or spongy, air has probably entered lash adjuster. If this occurs, check engine oil level. If engine oil level is okay, check oil screen and oil screen gasket for damage.
  4. After repairing cause of air leak, warm engine to operating temperature. Drive vehicle at low speed for approximately 5 minutes. Turn engine off for a few minutes.
  5. Restart engine and drive at low speed for approximately 5 minutes. Repeat this step several times for about one hour. This helps remove air from engine oil.

IGNITION TIMING

Note. Perform all adjustments with engine at normal operating temperature, cooling fan and accessories off, transmission in Park or Neutral, and front wheels in straight-ahead position. Set curb idle speed to specification. See IDLE SPEED SPECIFICATIONS table under IDLE SPEED & MIXTURE.

  1. Locate ignition timing adjustment connector. See «IGNITION TIMING ADJUSTMENT CONNECTOR LOCATION»(/mitsubishi/eclipse/i-1989-1995/remont/adjustments/#engine-controls-adjustments) table. Connect jumper wire between ignition timing adjustment connector and ground. Check ignition basic timing.
  2. If ignition basic timing is not within specification, loosen distributor (or crank angle sensor on engines with dual coil assembly) and rotate to adjust timing if necessary. See «IGNITION TIMING SPECIFICATIONS»(/mitsubishi/eclipse/i-1989-1995/remont/adjustments/#engine-controls-adjustments) table. Remove jumper wire from ignition timing adjustment connector. IGNITION TIMING SPECIFICATIONS (Degrees BTDC @ RPM) Application (1) Basic (2) (3) Actual 1.8L Eclipse 5 @ 600-800 10 @ 600-800 2.0L Eclipse 5 @ 650-850 8 @ 650-850 Galant SOHC 3-7 @ 650-850 10 @ 650-850 DOHC 3-7 @ 650-850 8 @ 650-850 DOHC Turbo 3-7 @ 700-900 12 @ 700-900 (1) With ignition timing adjustment connector grounded or vacuum hose (farthest from distributor) disconnected. (2) With ignition timing adjustment connector ungrounded or vacuum hose (farthest from distributor) connected. Ignition timing may fluctuate. (3) If vehicle altitude is more than 2300 ft. above sea level, actual timing may be advanced. IGNITION TIMING ADJUSTMENT CONNECTOR LOCATION Application (1) (2) Wire Color Location Eclipse Yellow/Red (3) Galant Yellow/Red (4) (1) Remove waterproof female connector (if equipped) for access to wire. (2) Ground connector at wire end for basic timing adjustment. (3) On main wiring harness, near wiper motor on firewall. (4) On main wiring harness, near master cylinder on firewall.

IDLE SPEED & MIXTURE

Note. Perform adjustments with engine at normal operating temperature, cooling fan and accessories off, transmission in Park or Neutral, and front wheels in straight-ahead position.

CURB (SLOW) IDLE SPEED

Note. Curb idle speed is controlled by Idle Speed Control (ISC) motor. Adjustment is usually not necessary. For curb idle speed specifications, see IDLE SPEED SPECIFICATIONS table under BASIC IDLE SPEED.

  1. Check ignition timing and adjust if necessary. See «IGNITION TIMING»(/mitsubishi/eclipse/i-1989-1995/remont/adjustments/#engine-controls-adjustments__ignition-timing) . Run engine at 2000-3000 RPM for more than 5 seconds. Allow engine to idle for 2 minutes. Check curb idle speed.
  2. If curb idle speed is not within specification, check ISC system. If ISC system is okay, adjust basic idle speed. See «BASIC IDLE SPEED»(/mitsubishi/eclipse/i-1989-1995/remont/adjustments/#engine-controls-adjustments__basic-idle-speed-eclipse) .

BASIC IDLE SPEED - ECLIPSE 1.8L & GALANT 2.0L SOHC

Note. ALWAYS check TPS adjustment after adjusting basic idle speed. See THROTTLE POSITION SENSOR (TPS) .

  1. Loosen throttle cable. Connect Multi-Use Tester (MUT) to diagnostic connector, located under left side of dash. Turn ignition on for more than 15 seconds. DO NOT start engine. Turn ignition off. This should fully retract ISC motor plunger.
  2. Disconnect harness connector(s) from Idle Speed Control (ISC) motor. Ensure ISC plunger is in fully retracted position. Unscrew fixed Speed Adjusting Screw (SAS) slightly. (Scheme 1) CAUTION: When cleaning throttle body, plug air by-pass hole in throttle body to prevent solvent from entering passage.
  3. Start engine. Select item No. 22 and read basic idle speed. See «IDLE SPEED SPECIFICATIONS»(/mitsubishi/eclipse/i-1989-1995/remont/adjustments/#engine-controls-adjustments) table. If basic idle speed is within specification, go to step 6). If basic idle speed is not correct, clean throttle body bore and throttle valve. Recheck basic idle speed.
  4. If basic idle speed is still incorrect after cleaning throttle body, adjust basic idle speed by turning idle Speed Adjusting Screw (SAS). (Scheme 1) After adjusting basic idle speed, turn fixed SAS screw clockwise until engine speed begins to increase.
  5. Turn fixed SAS screw counterclockwise until engine speed decreases. Turn fixed SAS screw counterclockwise an additional 1/2 turn from point at which engine speed no longer decreases. Turn off engine.
  6. Adjust throttle cable. Reconnect harness connector(s) at ISC motor. Start engine. Operate engine for about 5 minutes. Ensure engine idles within curb idle speed specification. See «IDLE SPEED SPECIFICATIONS»(/mitsubishi/eclipse/i-1989-1995/remont/adjustments/#engine-controls-adjustments) table.
  7. Turn ignition off. Disconnect negative battery cable for at least 10 seconds to clear diagnostic trouble code. Reconnect negative battery cable. Operate engine at idle for about 5 minutes to ensure engine idles smoothly.

BASIC IDLE SPEED - ECLIPSE & GALANT 2.0L DOHC

Note. ALWAYS check TPS adjustment after adjusting basic idle speed. See THROTTLE POSITION SENSOR (TPS) .

Scheme 1

Scheme 1: BASIC IDLE SPEED - ECLIPSE & GALANT 2.0L DOHC
Scheme 1: BASIC IDLE SPEED - ECLIPSE & GALANT 2.0L DOHC

Scheme 2

Scheme 2
Scheme 2
  1. Bring engine to normal operating temperature. Connect Multi-Use Tester (MUT) to diagnostic connector, located under left side of dash. Ground ignition timing adjustment connector, located below master cylinder. Start and run engine until it reaches normal operating temperature.
  2. Select item No. 22 and read idle speed. If idle speed is not correct, adjust by turning idle Speed Adjusting Screw (SAS). (Scheme 2) If idle speed is higher than normal, even with idle SAS fully tightened, check to see if idle position switch has been moved.
  3. Adjust idle position switch if it has been moved. See «IDLE POSITION SWITCH»(/mitsubishi/eclipse/i-1989-1995/remont/adjustments/#engine-controls-adjustments__idle-position-switch) under «THROTTLE POSITION SENSOR (TPS)»(/mitsubishi/eclipse/i-1989-1995/remont/adjustments/#engine-controls-adjustments). If idle position switch has not been moved, fast idle air valve may be leaking. Replace throttle body if fast idle air valve is leaking. IDLE SPEED SPECIFICATIONS Application Curb Idle Basic Idle 1.8L Eclipse 600-800 600-800 2.0L Eclipse, Galant (SOHC) & (DOHC) 650-850 650-850 Galant (DOHC Turbo) 700-900 700-900

FIXED SPEED ADJUSTING SCREW

Eclipse 2.0L and Galant 2.0L DOHC use an idle position switch as the fixed Speed Adjusting Screw (SAS). For adjustment, see IDLE POSITION SWITCH under THROTTLE POSITION SENSOR (TPS).

On all other models, fixed Speed Adjusting Screw (SAS) is preset by manufacturer and usually does not require adjustment. Only adjust fixed SAS if other adjustment procedures require it, or if manufacturer's original setting has been changed. To adjust fixed Speed Adjusting Screw (SAS), adjust basic idle speed. See BASIC IDLE SPEED under IDLE SPEED & MIXTURE.

IDLE MIXTURE

Note. Idle mixture is computer controlled on fuel injected engines and is nonadjustable. CO level specifications are not available from manufacturer.

TPS ADJUSTMENT

Note. Ensure basic idle speed is set to specification before adjusting TPS. See BASIC IDLE SPEED under IDLE SPEED & MIXTURE. Perform all adjustments with engine at normal operating temperature, front wheels in straight-ahead position, cooling fan and all accessories off, and transmission in Park or Neutral.

  1. Bring engine to normal operating temperature. On Precis, connect Digital Volt-Ohmmeter (DVOM) between throttle position sensor terminals No. 1 (Black wire) and 3 (Light Green wire), and between terminals No. 2 (Green/White wire) and 4 (Green/Black wire) on all others. Turn ignition on. DO NOT start engine. Note TPS output voltage. Output voltage should be .48-.52 volt.
  2. If output voltage is not correct, loosen TPS mounting screws and rotate TPS until output voltage is within specification. Tighten TPS mounting screws. Turn ignition off. Disconnect negative battery cable for at least 15 seconds to clear diagnostic trouble code. Reconnect negative battery cable.

IDLE POSITION SWITCH

Note. Idle position switch is preset by manufacturer. Adjustment is usually not necessary. If other procedures require adjustment of idle position switch or if switch setting has been changed, adjust switch as follows.

Scheme 3

Scheme 3: 2.0L DOHC Eclipse & 2.0L DOHC Galant
Scheme 3: 2.0L DOHC Eclipse & 2.0L DOHC Galant
  1. Loosen throttle cable. Disconnect electrical connector from idle position switch. (Scheme 3) Loosen lock nut at base of switch. Turn switch counterclockwise until throttle valve is fully closed.
  2. Connect ohmmeter between switch terminal and switch body (ground). Turn idle position switch clockwise until ohmmeter registers continuity. At this point, throttle valve should begin to open.
  3. Turn switch 15/16 of a turn beyond contact point. Tighten lock nut at base of idle position switch, holding switch to prevent it from turning while tightening.
  4. Adjust throttle cable. Adjust basic idle speed. See «BASIC IDLE SPEED»(/mitsubishi/eclipse/i-1989-1995/remont/adjustments/#engine-controls-adjustments__basic-idle-speed-eclipse) under IDLE SPEED & MIXTURE. Adjust TPS. See TPS ADJUSTMENT.

All Other Models

Idle position switch is incorporated into ISC motor and is automatically adjusted when TPS is adjusted. See TPS ADJUSTMENT .