1. The Basics (Easy Checks First):
* Fuel:
* Empty Tank? Sounds obvious, but worth checking.
* Fuel Filter: A clogged fuel filter restricts fuel flow. Replace it. It's cheap and easy.
* Fuel Pump: A weak or failing fuel pump won't deliver enough fuel under pressure. You can check fuel pressure with a gauge.
* Fuel Delivery Issues: Check the fuel lines for leaks or cracks.
* Ignition System:
* Spark Plugs & Wires: Worn, fouled, or loose spark plugs are a common cause. Inspect, clean, gap, and replace if necessary. Check the wires for cracks or damage.
* Distributor Cap & Rotor: Inspect for cracks, burns, or corrosion. Replace if necessary.
* Ignition Coil: A weak coil won't provide sufficient spark. Test it with a multimeter or replace it.
* Ignition Timing: Incorrect timing can cause rough running. You'll likely need a timing light to check this.
* Air Intake:
* Air Filter: A dirty air filter restricts airflow. Replace it.
* Vacuum Leaks: Small vacuum leaks can disrupt engine operation. Listen for hissing sounds near the intake manifold and vacuum lines.
2. More Advanced Troubleshooting (If the basics don't solve the problem):
* Carburetor: A poorly tuned or dirty carburetor is a likely culprit. This requires cleaning, rebuilding, or potentially replacement depending on its condition. This is often a complex task requiring specific knowledge and tools.
* Compression Test: Low compression in one or more cylinders indicates problems like worn rings, valve problems, or head gasket leaks.
* Vacuum Advance: If the vacuum advance in the distributor is malfunctioning, it will affect timing and cause rough running.
* Camshaft: While less likely, a worn camshaft can cause a rough idle and poor performance.
* PCV Valve: A malfunctioning Positive Crankcase Ventilation valve can lead to rough running.
3. Symptoms to Help Narrow it Down:
To get more specific help, describe the rough running:
* When does it happen? (Only at idle, under acceleration, at higher RPMs?)
* What are the symptoms? (Stalling, misfiring, backfiring, hesitation, rough idle, poor acceleration?)
* Any unusual noises? (Knocking, ticking, etc.)
* Recent modifications or repairs? (This can point to the source of the problem.)
4. Seeking Help:
* Mechanic: If you're not comfortable working on your car yourself, taking it to a mechanic specializing in classic cars is the best option. They have the experience and tools to diagnose and fix the problem efficiently.
* Online Forums: There are many online forums dedicated to classic Camaro restoration and repair. You can describe your issue and get advice from experienced enthusiasts.
Important Note: Working on a classic car like a 1969 Camaro Z28 can be challenging. Safety is paramount. Always disconnect the battery before working on the electrical system. If you're unsure about anything, seek professional help. Improper repairs can cause further damage.
