Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSCHEVROLET1998SUBURBAN K2500, 7.4 J, PART TIMEREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 337 (ENGINE CONTROLS TROUBLESHOOTING - NO CODES - 3.1L)SYMPTOMSHARD STARTSENSOR/SYSTEM
1998 Chevrolet Suburban K2500, 7.4 J, Part Time
Hard Start: Sensor/System
1998 Chevrolet Suburban K2500, 7.4 J, Part TimeSECTION Sensor/System
WARNING: This page is about a different car, the 2003 Pontiac Grand Prix, 2003 Chevrolet Malibu, and 2003 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.
- Check Engine Coolant Temperature (ECT) sensor for being shifted in value. Connect a scan tool and compare ECT with Intake Air Temperature (IAT) on a cold engine. The ECT and IAT should be within 5°F of each other. Check the resistance of the ECT sensor if the temperature is out of range with the IAT sensor. See TEMPERATURE VS. RESISTANCE table. If the ECT sensor resistance is not within specification, see DTC P0113: INTAKE AIR TEMPERATURE SENSOR CIRCUIT - HIGH VOLTAGE under DIAGNOSTIC TESTS in SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - 3.1L CENTURY, GRAND PRIX & MALIBU article. On Malibu, also see DTC P0117: ENGINE COOLANT TEMPERATURE SENSOR CIRCUIT - LOW VOLTAGE under DIAGNOSTIC TESTS in SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - 3.1L CENTURY, GRAND PRIX & MALIBU article.
- Monitor the 24X crank sensor and Camshaft Position (CMP) sensor signal present parameters on a scan tool. If both are not responding, test the sensor feed circuit. Both sensors use a separate feed circuit but are internally connected to power. Check all CKP sensor "A" and CMP sensor circuits for intermittents. See INTERMITTENTS .
- Monitor the 3X crank sensor parameter on the scan tool. If the 3X crank sensor parameter is not responding, check the CKP sensor and circuits for intermittents. Check the Ignition Control (IC) circuit, IC timing control circuit, low resolution engine speed signal circuit and the low reference circuit for intermittents. If these circuits become open, or shorted, they may not set a DTC immediately, but are capable of causing driveability complaints. See INTERMITTENTS .
- Check the Mass Airflow (MAF) sensor for proper installation and conditions. A MAF sensor with a damaged honeycomb may cause a hard start. Check the air intake ducts for being collapsed, damaged areas, looseness, improper installation, or leaking, especially between the MAF sensor and the throttle body.
- Using a scan tool, test the Idle Air Control (IAC) operation. Command the engine RPM to 1500 RPM and back to the starting RPM. If the engine RPM does not change when commanded, diagnose the IAC system. See DTC P0506: IDLE SPEED LOW and DTC P0507: IDLE SPEED HIGH under DIAGNOSTIC TESTS in SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - 3.1L CENTURY, GRAND PRIX & MALIBU article.
- Check the Exhaust Gas Recirculation (EGR) system for proper sealing/connections and operation. See EXHAUST GAS RECIRCULATION under EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM & COMPONENT TESTING - 3.1L CENTURY, GRAND PRIX & MALIBU article.
TEMPERATURE VS. RESISTANCE
| °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) | 12,300 |
| 14 (-10) | 16,180 |
| 5 (-15) | 21,450 |
| -4 (-20) | 28,680 |
| -22 (-30) | 52,700 |
| -40 (-40) | 100,700 |
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.