G20
Check engine compression at normal operating temperature at specified cranking speed. Release fuel pressure, and disconnect coil wire at distributor. Remove all spark plugs, and hold throttle wide open.
| Application | Specification |
|---|
| Compression Ratio | 9.5:1 |
| Normal Compression Pressure | (1) 178 psi (12.5 kg/cm 2 ) |
| Minimum Compression Pressure | (1) 149 psi (10.5 kg/cm 2 ) |
| Maximum Variation Between Cylinders | 14 psi (1.0 kg/cm 2 ) |
| (1) Measured at 300 RPM. |
COMPRESSION SPECIFICATIONS - 4-CYLINDER
J30
Check engine compression at normal operating temperature at specified cranking speed. Release fuel pressure, and disconnect crankshaft position sensor harness connector. Remove all spark plugs, and hold throttle wide open.
| Application | Specification |
|---|
| Compression Ratio | 10.5:1 |
| Normal Compression Pressure | (1) 186 psi (13.1 kg/cm 2 ) |
| Minimum Compression Pressure | (1) 142 psi (10.0 kg/cm 2 ) |
| Maximum Variation Between Cylinders | 14 psi (1 kg/cm 2 ) |
| (1) Measured at 300 RPM. |
COMPRESSION SPECIFICATIONS - V6
Q45
Check engine compression at normal operating temperature at specified cranking speed. Release fuel pressure, remove left air duct and disconnect power transistor connectors. Remove left harness connector bracket and ornamental rocker covers. Disconnect harness connector between ignition coil and power transistor. Remove ignition coil bracket and bracket with ignition coils. Remove all spark plugs, and hold throttle wide open.
| Application | Specification |
|---|
| Compression Ratio | 10.2:1 |
| Normal Compression Pressure | (1) 185 psi (13 kg/cm 2 ) |
| Minimum Compression Pressure | (1) 142 psi (10 kg/cm 2 ) |
| Maximum Variation Between Cylinders | 14 psi (1 kg/cm 2 ) |
| (1) Measured at 300 RPM. |
COMPRESSION SPECIFICATIONS - V8
VALVE CLEARANCE
Note. All vehicles are equipped with hydraulic lifters. No adjustments are required.
IGNITION COIL
| Application | Primary | Secondary |
|---|
| G20 | 1.0 | 10,000 |
| J30 | 0.9 | 8000 |
| Q45 | 0.7 | 8000 |
IGNITION COIL RESISTANCE - Ohms @ 68°F (20°C)
DISTRIBUTOR SENSORS
| Application | (1) Fluctuating Voltage |
|---|
| All Models | Between 5 And Zero |
| (1) Rotate crankshaft position sensor slowly by hand. Includes sub-crankshaft position sensor on Q45. |
| (1) | Rotate crankshaft position sensor slowly by hand. Includes sub-crankshaft position sensor on Q45. |
CRANKSHAFT POSITION SENSOR
HIGH TENSION WIRE RESISTANCE
| Application | Ohms |
|---|
| G20 | 30,000 Maximum |
| (1) Not applicable to J30 and Q45 distributorless ignition system. |
| (1) | Not applicable to J30 and Q45 distributorless ignition system. |
HIGH TENSION WIRE RESISTANCE (1)
SPARK PLUGS
| Application | NGK No. |
|---|
| All Models | PFR5B-11 |
| Application | Gap In. (mm) | Torque Ft. Lbs. (N.m) |
|---|
| All Models | .039-.043 (1.00-1.10) | 15-21 (20-29) |
SPARK PLUG SPECIFICATIONS (Platinum)
FIRING ORDER & TIMING MARKS
Note. For firing order (Scheme 1)- (Scheme 3). Q45 uses a distributorless ignition system. Firing order for Q45 is controlled by ECU through left and right power transistors. On G20 adjustments to timing are made by rotating distributor after loosening mounting bolts. On J30 and Q45 adjustments to timing are made by rotating crankshaft position sensor after loosening mounting bolts.
Firing Order (G20). Scheme 1
Scheme 1: Firing Order (G20)
Firing Order (J30). Scheme 2
Scheme 2: Firing Order (J30)
Firing Order (Q45). Scheme 3
Scheme 3: Firing Order (Q45)
IGNITION TIMING
| Application | (1) Specification |
|---|
| G20 | 13-17 @ 700-800 |
| J30 | 13-17 @ 670-770 |
| Q45 | 13-17 @ 600-700 |
| (1) See ADJUSTMENTS article in the ENGINE PERFORMANCE Section. |
| (1) | See ADJUSTMENTS article in the ENGINE PERFORMANCE Section. |
IGNITION TIMING (Degrees BTDC @ RPM)
FUEL PUMP
| Application | (1) psi (kg/cm 2 ) | (2) psi (kg/cm 2 ) |
|---|
| G20 | 36 (2.5) | 43 (3.0) |
| J30 & Q45 | 34 (2.4) | 43 (3.0) |
| (1) With vacuum hose connected at fuel pressure regulator. (2) With vacuum hose disconnected at fuel pressure regulator. |
| (1) | With vacuum hose connected at fuel pressure regulator. |
| (2) | With vacuum hose disconnected at fuel pressure regulator. |
INJECTOR RESISTANCE
| Application | Ohms |
|---|
| All Models | 10-14 |
INJECTOR RESISTANCE SPECIFICATIONS
IDLE SPEED
| Application | RPM |
|---|
| G20 | 700-800 |
| J30 | 645-695 |
| Q45 | 600-700 |
| (1) See ADJUSTMENTS article in the ENGINE PERFORMANCE Section. |
| (1) | See ADJUSTMENTS article in the ENGINE PERFORMANCE Section. |
IDLE SPEED SPECIFICATIONS (1)
THROTTLE POSITION SENSOR
| Application | (1) Volts |
|---|
| G20 |
| A/T Before Serial No. 450021 & M/T | 0.5-4.5 |
| A/T Serial No. 450021 & Later | 0.4-4.6 |
| J30 & Q45 | 0.4-4.6 |
| (1) Voltage variation from closed throttle (idle) to wide open throttle. |
| (1) | Voltage variation from closed throttle (idle) to wide open throttle. |
THROTTLE POSITION SENSOR SPECIFICATIONS
| Application | (1) Ohms |
|---|
| G20 (A/T Before Serial No. 450021 & M/T) |
| Completely Released | 2000 |
| Partially Released | 2000-10,000 |
| Completely Depressed | 10,000 |
| G20 (A/T Serial No. 450021 & Later) |
| Completely Released | 1000 |
| Partially Released | 1000-10,000 |
| Completely Depressed | 10,000 |
| J30 |
| Completely Released | 1700 |
| Partially Released | 1700-10,500 |
| Completely Depressed | 10,500 |
| Q45 |
| Completely Released | 700 |
| Partially Released | 700-5000 |
| Completely Depressed | 5000 |
| (1) Approximate. |
THROTTLE POSITION SENSOR RESISTANCE
