If your idle is too high or low, the problem isn't something you adjust manually. Instead, it points to an underlying issue that needs diagnosis. Potential causes include:
* Throttle Position Sensor (TPS): A faulty TPS sends incorrect information to the ECM, leading to incorrect idle control.
* Idle Air Control (IAC) valve: This valve regulates the air entering the engine at idle. A dirty or faulty IAC valve is a common cause of idle problems.
* Vacuum Leaks: Leaks in the vacuum system can affect the engine's idle.
* Mass Air Flow (MAF) sensor: If equipped (less likely on an '84), a malfunctioning MAF sensor can disrupt the air/fuel mixture and affect idle.
* ECM issues: While rare, the ECM itself could be faulty.
What you should do:
1. Don't try to adjust anything on the throttle body directly. You'll likely cause more damage.
2. Diagnose the problem. Start by checking for obvious vacuum leaks (listen for hissing sounds around the intake manifold and vacuum lines). A visual inspection of the throttle body and IAC valve for cleanliness is also a good idea. You may need a multimeter to test the TPS and IAC voltage and resistance.
3. Use a scan tool. A scan tool capable of reading OBDI codes (your '84 Camaro likely uses this older system) can reveal diagnostic trouble codes (DTCs) that pinpoint the problem. An auto parts store may be able to read codes for you.
4. Consult a repair manual: A Haynes or Chilton manual specific to your year and model Camaro will provide detailed information on troubleshooting and repair procedures.
5. Seek professional help: If you're not comfortable working on your car's fuel injection system, it's best to take it to a qualified mechanic. Incorrect adjustments or repairs can damage your engine.
In short, adjusting the idle on a fuel-injected 1984 Camaro 305 is not a simple adjustment; it requires proper diagnostics and potentially repair or replacement of components.
