Catalytic converters must be warm before they can work properly. On a cold start the PCM provides a rich mixture to keep the cold engine running.
All that extra fuel goes into the catalytic converter. But the exhaust isn't very hot, because, ah, the engine is pretty cold. GM has employed several strategies to fire up the catalytic converter quicker and reduce cold start emissions. One way is to use a secondary air pump that pumps outside air directly into the catalytic converter.
At this point we are assuming that the fuses and relays are good. You will need to locate the PCM/TCM and the power input signal circuit using your vehicle information source. Unplug the connector from the PCM/TCM, place the ignition switch in the ON position, and probe the appropriate circuit with the positive test lead of the DVOM.
The scent may C0079 signal oil or coolant leaking from their normally closed-loop systems, or it may indicate dangerous exhaust gases invading your car's interior. Car and truck exhaust contains toxic gases such C0079, so if the inside of your car ignition run/start circuit failure as if you were standing behind your car, get out and get it fixed. Fight the urge to take a little nap first. So sleepy. That's the carbon monoxide talking, friends. At least open a window on your way to the shop.
Difficulty Level (Easy)
Repair Time (20 Min.)
||Cost Prediction : $ 90-120|
C0079 is a kind of Chassis Trouble Code
Diagnosing chassis noises can be one of the most frustrating problems technicians face. Fortunately, manufacturers have engineered noise, vibration and harshness (NVH) diagnostic techniques and equipment to find the source of the noise.
You can view according C0079 DTC for your car model. We selected several models to see obd2 solutions click and view it.