Random misfires in cylinders 4 and 7 of a 2017 Chevrolet Tahoe can be caused by several issues. Here are some potential causes and steps you can take to diagnose and fix the problem: Ignition System Problems: Spark Plugs: Check the spark plugs for wear, fouling, or improper gaps. Replace them if they are old or damaged. Ignition Coils: Faulty ignition coils can cause misfires. You can swap the coils between cylinders to see if the misfire follows the coil, indicating a bad coil. Ignition Wires: Damaged or worn ignition wires can lead to misfires. Inspect them for any signs of wear or damage and replace them if necessary. Fuel System Issues: Fuel Injectors: Clogged or malfunctioning fuel injectors can cause misfires. Use a fuel injector cleaner or have the injectors professionally cleaned. You can also swap the injectors between cylinders to see if the misfire follows the injector. Fuel Pressure: Low fuel pressure can cause misfires. Check the fuel pressure with a gauge to ensure it is within the manufacturer’s specifications. Air Intake and Vacuum Leaks: Vacuum Leaks: Check for any vacuum leaks around the intake manifold, throttle body, and hoses. Use a smoke test or a carburetor cleaner spray to detect leaks. Air Filter: A dirty air filter can restrict airflow and cause misfires. Inspect and replace the air filter if it is dirty. Engine Mechanical Problems: Compression Issues: Low compression in cylinders 4 and 7 can cause misfires. Perform a compression test to check the compression levels in all cylinders. If the compression is low, it could indicate worn piston rings, damaged valves, or a blown head gasket. Timing Issues: Problems with the timing chain or belt can cause misfires. Check the timing to ensure it is set correctly. Electronic and Sensor Problems: Crankshaft and Camshaft Position Sensors: Faulty sensors can cause misfires. Use an OBD-II scanner to check for sensor-related trouble codes and replace the sensors if necessary. ECM/PCM Issues: The Engine Control Module (ECM) or Powertrain Control Module (PCM) could be malfunctioning. A professional diagnostic tool can help determine if the ECM/PCM is causing the misfire. Exhaust System Issues: Catalytic Converter: A clogged or damaged catalytic converter can cause backpressure, leading to misfires. Inspect the catalytic converter and replace it if necessary. Oxygen Sensors: Faulty oxygen sensors can cause incorrect fuel mixture adjustments, leading to misfires. Use an OBD-II scanner to check for oxygen sensor-related codes and replace the sensors if needed.
Not a professional but I had a problem with a 2014 chevy silverado that was pretty close to the same thing. The problem wound up being deteriorated catalytic converter on th right side. It took me a while to figure it out.
Not a professional but I had a problem with a 2014 chevy silverado that was pretty close to the same thing. The problem wound up being deteriorated catalytic converter on th right side.
I had a 2017 Tahoe. key word is had... I am not a mechanic but could it be possible the spark plug wires be going to the wrong cylinder? i dont know just want to add my 2 pennies which aint worth nothing
