Chevrolet Cruze P0301 diagnose and fix
Shops are reporting a high incidence of Chevrolet Cruze P0301 issues. Obviously, your first test should be directed to the spark plug for cylinder #1. Proper plug type and torque are critical to the proper operation of the spark plug. Over torque can distort the metal shell, causing a leak which results in misfires. Plus, over torquing the spark plug can cause the cylinder head threads to pull out of the head. Under torque, on the other hand, can cause the spark plug to be ejected from the engine, taking the spark plug threads with it.
Common issues that cause a Chevrolet Cruze P0301 trouble code
Start by removing the ignition coil connector and checking for corrosion or melting. Some shops are reporting that the coil electrical connector has melted, so check that first. The high temperatures are often caused by corroded terminals in the connector.
Next, check the rubber boot and connector that attaches to the spark plug. Shops are also reporting water leaks that result in corrosion.
If the plastic connector is good, the next thing to check is the DC power on violet/blue wire in terminal 4 of the #1 ignition coil connector (Powertrain Main Relay Fused Supply 2). Check the #4 terminal at all ignition coils and compare (connector removed and IGN key ON). The voltage at all four connectors should be the same. This is the supply voltage to all four coils. If the violet/blue wire voltage doesn’t match, check for a short to voltage between the ECM and the IGN coil. Next, check the low voltage reference and ignition control switching. See how the coil works, below. If all the powers and connectors check out, replace the coil.
How the ignition coil works
The coil-on-plug (COP) ignition coils used in this engine have internal control using a solid state driver to turn power on and off (energize on/off) to the primary coil. So each coil has a voltage feed and ground circuit and a ignition control (IC) low reference (Black/Blue wire) and an ignition control (blue/red) wire.
1 BK Ground
2 Black/Blue Ignition Control Low Reference Bank
3 Blue/red Ignition Control
4 Violet/blue Powertrain Main Relay Fused Supply
©, 2019 Rick MuscoplatPosted on by Rick Muscoplat