1996 Saturn Fix Cylinder 1 Misfire

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Misfires are a common problem among cars, particularly older ones, when a lack of spark, fuel, air or compression occurs. Diagnosing and fixing a misfire takes skill because of the multiple components involved in the control of just one necessary element of combustion. Modern cars such as a 1996 Saturn have an on-board diagnostics system that can help find the source of the problem quickly if one is detected by a sensor. Misfires are characterized by a rough idle, reduction in power and poor riding comfort at speed and require immediate attention to avoid serious engine damage.

Tools Used[edit]

Tools
Adjustable wrench
On-board diagnostics scanner
Socket set
Anti-seize compound
Flashlight
Multimeter
Compression tester

Fix Cylinder 1 Misfire[edit]

  • Open the hood and disconnect the negative terminal from the battery using a wrench. Set it safely aside.
  • Hook up an on-board diagnostics scanner to the Saturn's on-board diagnostics II port. This is usually located under the driver's steering wheel column on either side. Turn the car to accessory and enter the scan mode of the scanner. Search for codes indicating injector, fuel or air delivery failure and replace components as necessary. Also scan for oxygen sensor codes giving higher than normal readings; these indicate a possible spark delivery problem.
  • Remove the cylinder 1 spark plug with a socket set and check it for discoloration using a spark plug color chart. Dry plugs indicate a lack of fuel, while wet spark plugs indicate a lack of spark. Replace the spark plug with a new one, ensuring to coat the threads in anti-seize compound.
  • Inspect the cylinder 1 spark plug wires from the distributor to the spark plug for cracking and exposed metal. These change the resistance in the wire, causing spark failure. If replacement is necessary, order an entire set and replace all spark plug wires to maintain uniform resistivity to all cylinders. Also check the distributor for signs of wear and replace as needed.
  • Remove the cylinder 1 injector connector at the wiring harness and inspect for corrosion or wiring damage and repair as needed. Check the resistance of the injector by attaching multimeter clips to the injector's metal connectors and turning the multimeter to the 200-ohm setting. Compare with the manufacturer's specification for that particular injector to ensure the electrical components are working.
  • Reinstall the cylinder 1 fuel injector clip. Remove the entire fuel rail with the injectors attached and coil wire. Turn the car over with the fuel rail off and inspect the spray pattern of the cylinder 1 injector. If a fine spray does not come from the injector, have it professionally cleaned or replace it.
  • Run a compression check whether the misfire continues. Use a compression tester specifically for car motors. Poor compression indicates a leak in the cylinder and will most likely mandate a check of the valve train or an engine rebuild.

Tips & Warnings[edit]

  • Use deep-well sockets and universal joints to remove hard-to-reach spark plugs.
  • Never work on the car's electrical components without first unplugging the battery as this can cause wiring harness damage and electrocution.
  • Only use copper spark plugs in these saturns or they will misfire. The newer platinum plugs and newer coils cause a camshaft code to be set and misfire