Engine Compression
Check compression pressure with battery fully charged, engine at normal operating temperature, throttle fully open, and engine at cranking speed.
NOTE:
On 528i models, deactivate the fuel Injection system by pulling connection "1" at the coil prior to making compression test.
COMPRESSION SPECIFICATIONS
| Application | Pressure | |
|---|---|---|
| Bavaria, 3.0 CS, 3.0 Si, 528i, 530i & 630CSi | ||
| Good | Above 156 psi (11 kg/cm2 ) | |
| Normal | 142-156 psi (10-11 kg/cm2 ) | |
| Poor | Below 142 psi (10 kg/cm2 ) | |
| 633CSi & 733i | ||
| Good | Above 142 psi (10 kg/cm2 ) | |
| Normal | 121-142 psi (8.5-10 kg/cm2 ) | |
| Poor | Below 121 (8 kg/cm2 ) | |