Engine Compression

Deactivate fuel injection system by removing DME master relay and fuel pump relay before performing compression test. See DME & FUEL PUMP RELAY LOCATION table. Ensure battery is fully charged.
Ensure engine coolant temperature does not exceed 95°F (35°C). Turn fasteners (2) on electric lead cover 90 degrees, and remove electric lead cover. Disconnect spark plug connectors.
Using 16-mm Socket (12 1 171) and Torque Limiter (12 1 172), remove spark plugs. Use Pressure Gauge (11 0 162), Test Adapter (11 0 166), and Tube Extension (11 0 167) to check compression pressure.

DME & FUEL PUMP RELAY LOCATION

Application

Location

All Models

⁽¹⁾ Behind Cover, Along Engine Compartment Firewall

⁽¹⁾	The first relay (viewed from left to right) is the DME master relay, followed by the fuel pump relay, and then the oxygen sensor heating relay.

COMPRESSION SPECIFICATIONS

Application	Specification
Compression Ratio - All Models	10.0:1
Compression Ratio - All Models	142-156 psi (10-11 kg/cm² )