Calibration Test
Connect a calibrated, reliable tach-dwell meter to vehicle ignition system. Operate engine at various speeds (RPM). See TACHOMETER ALLOWABLE VARIATION . If comparison between tach-dwell meter and vehicle tachometer readings are not within permissible variation, replace vehicle tachometer.
TACHOMETER ALLOWABLE VARIATION
| Engine Speed (RPM) | Allowable Variation (RPM) |
|---|---|
| 1000 | 900-1100 |
| 3000 | 2850-3150 |
| 5000 | 4750-5250 |
| 6000 | 5700-6300 |