Contents Wiring diagrams Section: Adjustments All sections

Engine Controls - Adjustments: Other Dodge Stealth I

Adjustments 3 illustrations ~1155 words

ENGINE MECHANICAL

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

VALVE CLEARANCE

Note. Diamante, Stealth and 3000GT models use hydraulic lash adjusters, valve adjustment is not necessary.

CHECKING HYDRAULIC VALVE LIFTERS

  1. Warm engine to normal operating temperature. Remove valve cover. Position cylinder No. 1 at TDC on compression stroke. Check intake rockers on cylinders No. 1 and 2. Check exhaust rockers on cylinders No. 1 and 3.
  2. Push downward on end of rocker arm above lash adjuster. Rotate crankshaft 360 degrees and check intake rockers on cylinders No. 3 and 4. Check exhaust rockers on cylinders No. 2 and 4. 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.

Note. Adjustment of ignition timing cannot be performed on vehicles equipped with Distributorless Ignition Systems (DIS). If ignition timing is not within specification, see CRANKSHAFT POSITION SENSOR in SYSTEM/COMPONENT TESTS article in this section.

  1. Locate ignition timing adjustment connector. See «IGNITION TIMING ADJUSTMENT CONNECTOR LOCATION»(ref-18898-S02984847192001010800000) 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 and rotate to adjust timing if necessary. See «IGNITION TIMING SPECIFICATIONS»(ref-18898-S17027904302001010800000) table. Remove jumper wire from ignition timing adjustment connector. IGNITION TIMING SPECIFICATIONS (Degrees BTDC @ RPM) Application (1) Basic (2) (3) Actual 3.0L Diamante 3-7 @ 600-800 15 @ 600-800 Stealth & 3000GT 2-8 @ 600-800 15 @ 600-800 (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. NOTE: Ignition timing adjustment connector is either round or oval with protective cover. Connector is either Black or Brown and is secured to harness with colored transparent tape. IGNITION TIMING ADJUSTMENT CONNECTOR LOCATION Application (1) (2) Wire Color Location Diamante White/Yellow (3) Stealth (SOHC & DOHC) Black/Green (4) 3000GT Black/Green (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 center of firewall. (4) On main wiring harness, near wiper motor on firewall, behind battery.

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 Air Control (IAC) 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»(ref-18898-S23502871002001010800000) . 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 IAC system. See «SYSTEM/COMPONENT TESTS»(ref-18918) article in this section. If IAC system is okay, adjust basic idle speed. See «BASIC IDLE SPEED»(ref-18898-S38513195132001010800000) .

BASIC IDLE SPEED

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

Note. For Data Link Connector (DLC) location, see TESTS W/CODES article in this section.

Note. Ensure vehicle is at normal operating temperature with all lights, cooling fan and accessories off. Shift transmission into Neutral or Park position.

Scheme 2

Scheme 2: BASIC IDLE SPEED

Scheme 3

Scheme 3
  1. Insert paper clip or appropriate probe into tachometer connector. See «TACHOMETER CONNECTOR LOCATION»(ref-18898-S11886260322001010800000) table. Connect a primary voltage detecting type tachometer to paper clip.
  2. Connect a jumper wire between data link terminal No. 10 and vehicle ground. (Scheme 2) Connect a jumper wire between ignition timing adjustment connector and vehicle ground. See «IGNITION TIMING ADJUSTMENT CONNECTOR LOCATION»(ref-18898-S02984847192001010800000) table under IGNITION TIMING.
  3. Start and run engine at idle. Check basic idle speed. See «IDLE SPEED SPECIFICATIONS»(ref-18898-S34031392842001010800000) table. If idle speed is not within specifications, turn engine speed adjusting screw until correct engine speed is obtained. (Scheme 3) Access to speed adjusting screw is obtained by removing rubber plug on throttle body.
  4. If idle speed cannot be lowered by adjusting engine speed adjusting screw, determine if fixed speed adjusting screw (stop screw contacting throttle lever) has been adjusted. See «FIXED SPEED ADJUSTING SCREW»(ref-18898-S10033492522001010800000) for procedure.
  5. After all adjustments are verified correct, possible cause of incorrect idle speed is deterioration of fast idle air control motor. Throttle valve must be replaced to correct symptom. Disconnect jumper wires and recheck idle speed. TACHOMETER CONNECTOR LOCATION Application Type Location Diamante 1- Or 3-Pin (1) Stealth, 3000GT 3-Pin (2) (3) (1) On SOHC & DOHC engine, 1-pin Blue connector is attached to main harness on center of firewall. 3-pin connector is mounted to ignition coil bracket and must be backprobed. (2) On SOHC, backprobe double wire portion of connector to noise filter (White/Black wire) behind intake plenum, near ignition coil. (3) On DOHC, blue connector (Black/White wire) below wiper motor. IDLE SPEED SPECIFICATIONS Application Curb Idle Basic Idle 3.0L 600-800 600-800

FIXED SPEED ADJUSTING SCREW

Note. Fixed Speed Adjusting Screw (FSAS) is preset by manufacturer and usually does not require adjustment. Only adjust FSAS if other adjustment procedures require it, or if manufacturer's original setting has been changed.

Scheme 4

Scheme 4: FIXED SPEED ADJUSTING SCREW
  1. Loosen throttle cable. Loosen FSAS lock nut. (Scheme 4) Turn FSAS counterclockwise until throttle valve is fully closed. Turn FSAS clockwise until throttle valve begins to open. Turn FSAS clockwise 1 1/4 turns after throttle valve begins to open.
  2. Tighten lock nut while holding FSAS in position. Adjust throttle cable. Adjust basic idle speed. See «BASIC IDLE SPEED»(ref-18898-S38513195132001010800000) under IDLE SPEED & MIXTURE. Adjust throttle position sensor. See «THROTTLE POSITION SENSOR (TPS)»(ref-18898-S08460023052001010800000).

IDLE MIXTURE

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

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.

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