Hard Start: Sensor/System
WARNING: This page is about a different car, the 2003 Chevrolet Corvette. However, it is still accessible from the selected car via links, so may be relevant.
- Verify that the Engine Coolant Temperature (ECT) sensor is not shifted in value. Connect a scan tool. Compare the engine coolant temperature to the Intake Air Temperature on a cold engine. The ECT and IAT sensor values should be within 5°F of each other. If the ECT sensor is out of range with the IAT sensor, measure the resistance of the ECT sensor. See TEMPERATURE VS RESISTANCE .
- Inspect the Mass Air Flow (MAF) sensor installation. A MAF sensor that is incorrectly installed may cause a hard start.
- Inspect the Camshaft Position (CMP) sensor for proper mounting and/or a bad connection. An extended crank occurs if the PCM does not receive a CMP signal.
NOTE:
The embossed arrows on the MAF sensor indicate the direction of the intake air flow. The arrows must point toward the engine. Install the MAF in the proper direction.
TEMPERATURE VS RESISTANCE
| Temperature °F (°C) | Ohms |
| 302 (150) | 47 |
| 284 (140) | 60 |
| 266 (130) | 77 |
| 248 (120) | 100 |
| 230 (110) | 132 |
| 212 (100) | 177 |
| 194 (90) | 241 |
| 176 (80) | 332 |
| 158 (70) | 467 |
| 140 (60) | 667 |
| 122 (50) | 973 |
| 113 (45) | 1188 |
| 104 (40) | 1459 |
| 95 (35) | 1802 |
| 86 (30) | 2238 |
| 77 (25) | 2796 |
| 68 (20) | 3520 |
| 59 (15) | 4450 |
| 50 (10) | 5670 |
| 41 (5) | 7280 |
| 32 (0) | 9420 |
| 23 (-5) | 12300 |
| 14 (-10) | 16180 |
| 5 (-15) | 21450 |
| -4 (-20) | 28680 |
| -22 (-30) | 52700 |
| -40 (-40) | 100700 |