Idle Control System
- Make
- Rover
- Model
- 600 Rover 600 Repair Manual - Volumes 1 and 2 - 2nd Edition
- Section
- Fault finding › Idle Control System
Engine management system – PGM-FiIdle Control System
Idle Control System
Note: Use TestBook or Microcheck to test the system.
How to use the symptom charts
- Across each row in the chart, the sub – systems that could be sources of a symptom are ranked in the order they should be inspected, starting with 1.
- Find the symptom in the left column, read across to the most likely source, then refer to the page listed at the top of that column. If inspection shows the system is OK, try the next system 2, etc.
| Symptom | Idle adjusting screw | Idle air control valve | A/C signal | Alternator signal | Gear position signal (Auto) | Starter switch signal | Fast idle thermo valve | Hoses/connections |
|---|---|---|---|---|---|---|---|---|
| Difficult to start when cold | 1 | |||||||
| Erratic fast idle | 3 | 2 | 1 | |||||
| Rough idle | 2 | 1 | ||||||
| When warm engine speed to high | 3 | 1 | 2 | 3 | ||||
| With warm engine, idle speed is low (no load) | 2 | 1 | ||||||
| With engine warm idle speed does not increase after starting engine | 1 | |||||||
| When in gear idle speed drops (Auto) | 2 | 1 | ||||||
| Idle speed drops when A/C is on | 2 | 1 | ||||||
| Erratic idle speed with changing electrical loads | 2 | 1 | ||||||
| Frequent stalling while warming up | 1 | |||||||
| Frequent stalling after warming up | 1 | |||||||
| Fails emission test | 1 |
Note: If the idle speed is out of specification and the instrument warning light does not blink Diagnostic Trouble Code (DTC) 14, check the following items:
- Idle speed adjustment.
- Air conditioning signal.
- Alternator FR signal.
- A/T gear position signal.
- Starter switch signal.
- Fast idle thermo valve.
- Vacuum hoses and connections.
- IAC valve and its mounting O – rings.
If no fault is found with the above items, substitute a known good IAC valve and readjust the idle speed. If the idle speed still cannot be adjusted to specification (and the instrument warning light does not blink Diagnostic Trouble Code (DTC) 14) after the IAC valve replacement, substitute a known good ECM and recheck. If the symptom goes away, replace the original ECM.
Original page
Parts & tools for this job For Rover 600
- PARTEngine gasket setSearch: Rover 600 engine gasket set
- TOOLTorque wrenchSearch: 3/8 inch torque wrench
- TOOLFeeler gauge setSearch: feeler gauge set
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