Mechanical Inspection: Compression

WARNING: This page does not describe the selected car, but rather 10 other vehicles, including the 2002 Mazda Tribute, 2002 Mazda Protege5, 2002 Mazda Protege, 2002 Mazda Millenia, and 2002 Mazda MX-5 Miata. However, it is still accessible from the selected car via links, so may be relevant.

Check engine mechanical condition with a compression gauge, vacuum gauge, or an engine analyzer. Ensure oil level and condition are okay. Ensure battery is fully charged. See engine analyzer manual for specific instructions.

WARNING: DO NOT use ignition switch during compression tests on fuel injected vehicles. Use a remote starter to crank engine. Fuel injectors on many models are triggered by ignition switch during cranking, which can create a fire hazard or contaminate the engine's oiling system.

COMPRESSION SPECIFICATIONS

Application

Minimum psi (kg/cm² ) @ RPM

Standard psi (kg/cm² ) @ RPM

B2300, B3000 & B4000

⁽¹⁾

Miata ⁽²⁾

146 (10.3) @ 300

209 (14.7) @ 300

Millenia ⁽²⁾

2.3L

121 (8.5) @ 250

164 (11.5) @ 250

2.5L

132 (9.3) @ 300

189 (13.3) @ 300

MPV

⁽¹⁾

Protege & Protege5 ⁽²⁾

119 (8.4) @ 300

171 (12.0) @ 300

Tribute

⁽¹⁾

626 ⁽²⁾

2.0L

119 (8.4) @ 300

171 (12.0) @ 300

2.5L

141 (9.9) @ 250

202 (14.2) @ 250

⁽¹⁾	Lowest compression reading should be within 75 percent of highest compression reading.

⁽²⁾	Difference between cylinders should not be more than 28 psi (2.0 kg/cm² ).