Tune-Up - 2.8l v6 VIN [z] Chevrolet Camaro II

VEHICLE IDENTIFICATION NUMBER (VIN) CODE

Engines may be identified by the 8th letter of Vehicle Identification Number (VIN). The VIN is located at the left front corner of instrument panel and is visible through windshield.

VIN ENGINE CODES

TUNE-UP NOTES

Note. When performing tune-up procedures described in this article, the following notes and precautions must be followed

With the exception of initial ignition timing, normal tune-up adjustments are not required. Perform adjustments only when indicated by the Computer Command Control (CCC) System Performance Check, CCC diagnostic charts and/or poor engine performance. See appropriate article in COMPUTER ENG CONTROL section for diagnostic information.

Due to late changes and corrections, always refer to Engine Tune-Up Decal in engine compartment before tune-up. If manual and decal specifications are different, always use specifications on Engine Tune-Up Decal.

Before making a compression test or cranking engine with a remote starting switch, disconnect ignition switch "BATT" terminal lead at distributor.

Do not remove spark plug wires with engine running. HEI secondary voltage may inflict harmful electrical shock.

Damage to HEI electronic module and/or ignition coil may result if "TACH" terminal in distributor cap connector is grounded.

ENGINE COMPRESSION

Test compression pressure with engine at normal operating temperature. Remove all spark plugs. Set throttle and choke valves wide open.

COMPRESSION SPECIFICATIONS

VALVE CLEARANCE SPECIFICATIONS

VALVE CLEARANCE ADJUSTMENT - HYDRAULIC LIFTERS

VALVE ARRANGEMENT

1. Left bank (Front-to-Rear) - E-I-I-E-I-E
2. Right bank (Front-to-Rear) - E-I-E-I-I-E

SPARK PLUG SPECIFICATIONS

SPARK PLUG TYPE

SPARK PLUG INSTALLATION

HIGH TENSION WIRE RESISTANCE

Carefully remove ends of wire from spark plug and distributor. Using an ohmmeter, check resistance while gently twisting wire. If resistance is not to specification, or fluctuates, replace wire.

WIRE RESISTANCE (OHMS)

DISTRIBUTOR

All models are equipped with High Energy Ignition (HEI) system with Electronic Spark Timing (EST) and no adjustment is required.

2.8L Firing Order & Timing Marks. Scheme 26

IGNITION TIMING

Note. Engines are equipped with a receptacle for a magnetic probe timing meter, located at 9.5° ATDC. Do not use this location for timing with a conventional light.

Check ignition timing with engine warm. Disconnect 4-wire connector at distributor. Set timing with engine idling.

IGNITION TIMING SPECIFICATIONS

With A/C

1. Warm engine to normal operating temperature. Check timing and adjust if necessary. Disconnect and plug vacuum hoses at EGR valve and canister purge control valve. Plug purge hose. Disconnect wire to idle solenoid. Place man. trans. in Neutral and auto. trans. in "D".
2. Adjust idle speed screw to curb idle RPM. Disconnect compressor clutch wire and turn A/C on to coldest setting. Open throttle slightly to allow plunger to extend. Turn solenoid screw to obtain correct RPM. Reconnect compressor clutch wire and all hoses.

Without A/C

1. Warm engine to normal operating temperature. Check timing and adjust if necessary. Disconnect and plug vacuum hoses at EGR valve and canister purge control valve. Plug purge hose. Disconnect wire to idle solenoid. Place man. trans. in Neutral and auto. trans. in "D".
2. Adjust idle speed screw to obtain curb idle RPM. Connect solenoid wire and open throttle to allow plunger to extend. Turn solenoid screw to obtain correct RPM. Reconnect hoses.

CURB IDLE SPEED (RPM)

THROTTLE POSITION SENSOR ADJUSTMENT

Disconnect TPS connector and jumper all 3 sensor terminals to harness. Connect a high impedance digital voltmeter to the center and bottom terminals of TPS. With ignition on and throttle in specified position, turn TPS adjusting screw until specified voltage is reached. Remove jumpers and reconnect harness.

TPS ADJUSTMENT VOLTAGE

TPS Adjustment Location For E2SE. Scheme 27

TPS Adjustment Location For E2ME & E4ME. Scheme 28

IDLE MIXTURE ADJUSTMENT

Note. Idle mixture adjustment is not normally necessary. Mixture should be checked only if vehicle fails testing or carburetor has been disassembled.

MIXTURE SCREW PLUG REMOVAL

1. Remove carburetor from engine, invert carburetor and drain fuel into a container. Place carburetor on a holding fixture with manifold side up.
2. Use hacksaw to make 2 small cuts below mixture plugs on bottom of throttle body. Use flat punch or chisel to break out a piece of throttle body to gain access to plugs.
3. Use a punch to drive out plug. If hardened steel plug shatters, remove loose pieces.
4. Repeat steps 2) and 3) to remove remaining plug (if equipped).

E2SE Only

1. Remove carburetor and remove mixture screw plug. Turn screw in until lightly seated, then back out 4 turns.
2. Remove vent stack screen. Turn part throttle lean mixture screw in until lightly seated and back out 2 1/2 turns. Reinstall carburetor without air cleaner.
3. Disconnect bowl vent line. Disconnect and plug vacuum hose at "T" in vent line (if used). Disconnect EGR valve and canister purge at carburetor and plug ports. Remove secondary vacuum break thermal vacuum switch from air cleaner, disconnect hot air valve hose from air cleaner, and plug switch. Leave all other hoses connected.
4. Connect tachometer to Brown connector and dwell meter to Green connector near carburetor. Set dwell meter on 6-cylinder setting. Run engine for at least 3 minutes or until dwell reading begins to vary.
5. Run engine at 3000 RPM and adjust lean mixture screw to achieve 35° dwell. Allow dwell to stabilize between adjustments. Return to idle.
6. Adjust idle mixture screw to obtain dwell reading of 25° while cooling fan is off. Allow readings to stabilize between adjustments. Disconnect mixture control solenoid while cooling fan is off and check for drop of at least 50 RPM.
7. Repeat 3000 RPM check and adjustment procedure if necessary. When dwell readings are correct, reconnect system hoses, replace vent screen, and remove test equipment.

E2SE Lean Mixture Screw Location. Scheme 29

Scheme 30

1. Mixture control solenoid should be checked before adjustment. Stop engine and remove air cleaner. Insert thin metal scale in "D" shaped hole in air horn. Press down to determine travel of solenoid. Total movement should be 1/16 - 3/16". NOTE: If solenoid movement is not correct, carburetor must be disassembled. See Rochester E2ME and E4ME Carburetor articles in FUEL SYSTEMS section for adjustment procedures.
2. To adjust idle air bleed valve, set parking brake and block drive wheels. Check ignition timing and adjust if necessary.
3. Connect tachometer to engine. Connect a dwell meter to lead wire from mixture control solenoid in carburetor. Set dwell meter on 6-cyl. scale. Start engine and run at idle until normal operating temperature is reached and a varying dwell is noted on dwell meter. NOTE: Engine must be run long enough to ensure that engine coolant sensor and oxygen sensor are at normal operating temperature.
4. Adjust curb idle speed (on models with ISC or ILC, do not adjust). With engine idling in "D" (auto. trans.) or neutral (man. trans.), observe dwell reading. If dwell needle is moving within 10-50°, no adjustment is necessary. If needle is fixed at one point or if it is outside this range, see SYSTEM PERFORMANCE CHART in the appropriate TESTS/CODES article in the COMPUTER ENG CONTROLS section. Return to next step if flow charts indicate carburetor adjustments, calibration or service are necessary.
5. With engine stopped, cover carburetor air intakes and vents with tape. Drill rivet heads on idle air bleed plug (above primary bores). Remove plug and blow out metal chips and rivet pieces. Start engine, run until warm, and adjust idle air bleed valve with screwdriver until dwell varies within 25-35° range. CAUTION: Perform this step carefully. The idle air bleed valve is very sensitive in controlling air/fuel ratios and should be turned only in 1/8 turn increments. (Scheme 30): E2ME & E4ME Idle Air Bleed Valve Location
6. If dwell reading does not vary and is not within the 25-35° range after this adjustment, remove carburetor. Remove mixture needle plugs and adjust the idle mixture as follows
7. Turn screws until lightly seated. Back out screws 3 turns. Reinstall carburetor and check dwell when engine is warm.
8. If dwell is below limits turn screws out in 1/8 turn increments. If above limits, turn screws in at 1/8 turn increments. Readjust air bleed valve to center dwell within limits. Reset idle speed if necessary. Remove all test equipment and reconnect all hoses.

COLD (FAST) IDLE RPM

Disconnect and plug vacuum hoses at EGR valve and canister purge valve. Plug purge hose. With engine at normal operating temperature, place fast idle screw on high step of cam. Set fast idle speed using fast idle screw. Reconnect hoses.

FAST IDLE SPEED (RPM)

AUTOMATIC CHOKE

The choke cover is riveted on in a fixed position and no adjustment is necessary or possible.

FUEL PUMP

Make all tests at slow idle speed. For models with fuel return line, pinch off return line. For vacuum test, connect vacuum gauge to inlet side of pump.

FUEL PUMP PERFORMANCE

All models use a Delco-Remy High Energy Ignition with Electronic Spark Timing (HEI-EST).

IGNITION COIL RESISTANCE (OHMS)

PICK-UP COIL RESISTANCE (OHMS)

FUEL SYSTEM

CARBURETORS

BATTERY

BATTERY SPECIFICATIONS

STARTER

All models are equipped with a Delco-Remy solenoid actuated starter with overrunning clutch.

STARTER SPECIFICATIONS

ALTERNATOR REGULATOR

All models except 27SI use a Delco-Remy non-adjustable regulator, integral with alternator. The 27SI uses a Delco-Remy adjustable regulator, integral with alternator.

REGULATOR OPERATING VOLTAGE

ALTERNATOR SPECIFICATIONS

SERVICE INTERVALS

REPLACEMENT INTERVALS

BELT ADJUSTMENT SPECIFICATIONS

BELT ADJUSTMENT SPECIFICATIONS (1)

CAPACITIES

COOLING CAPACITIES (1)

ENGINE OIL & FUEL CAPACITIES

TRANSMISSION & DIFFERENTIAL CAPACITIES