Diagnostic Aids
Check sensor and PCM electrical connection for corrosion. Using scan tool, check for a shifted MAP sensor. See MAP SENSOR VOLTAGE RANGE table. Compare this reading to a known-good vehicle with the same sensor. Readings should be within 0.4 volt.
An intermittent malfunction may be caused by a poor connection, rubbed-through wire insulation, or a wire broken inside insulation. Inspect harness connectors for backed-out terminals, improper mating, broken locks, improperly formed or damaged terminals, or poor terminal-to-wire connections before replacing component.
MAP SENSOR VOLTAGE RANGE
| Altitude (Feet) | Range (Volts) |
|---|---|
| Less Than 1000 | 3.8-5.5 |
| 1000-2000 | 3.6-5.3 |
| 2000-3000 | 3.5-5.1 |
| 3000-4000 | 3.3-5.0 |
| 4000-5000 | 3.2-4.8 |
| 5000-6000 | 3.0-4.6 |
| 6000-7000 | 2.9-4.5 |
| 7000-8000 | 2.8-4.3 |
| 8000-9000 | 2.6-4.2 |
| 9000-10,000 | 2.5-4.0 |