Variance Test
Connect a test tachometer to engine. Start engine and compare vehicle tachometer reading with test tachometer. See TACHOMETER ALLOWABLE VARIATION table for tachometer allowable error.
TACHOMETER ALLOWABLE VARIATION
| Standard Indication | Allowable Range |
|---|---|
| 950 RPM | 900-1000 RPM |
| 1950 RPM | 1900-2000 RPM |
| 2950 RPM | 2900-3000 RPM |
| 3950 RPM | 3900-4000 RPM |
| 4950 RPM | 4900-5000 RPM |
| 5950 RPM | 5900-6000 RPM |
| 6950 RPM | 6900-7000 RPM |