Diagnostic Aids
After engine is started, temperature should rise steadily to about 203°F (95°C) and then level off when thermostat opens.
If Codes 14 and 21 are stored at same time, an open could exist in Gray/Yellow wire. An out-of-calibration CTS may cause poor driveability. Use temperature and resistance values of CTS from COOLANT TEMPERATURE SENSOR RESISTANCE table to check for an out-of-calibration sensor. If code is intermittent, refer to TESTS W/O CODES article in this section.
COOLANT TEMPERATURE SENSOR RESISTANCE
| Temperature °F (°C) | Ohms |
|---|---|
| 210 (99) | 190 |
| 160 (71) | 400 |
| 100 (38) | 1250 |
| 70 (21) | 2350 |
| 40 (4) | 4780 |
| 20 (-7) | 8100 |
| 0 (-18) | 14,650 |