How can I tell if my PCM is leaking fuel?
The injector driver inside the PCM responds to this condition with an extended duty cycle or a direct close of the driver causing the injector or group of injectors to dump fuel inside the engine. By removing each cylinder spark plug and checking their condition (black or wet with fuel) you can identify the afflicted cylinders.
Why does my engine have a lean reading?
Step 4 – An exhaust leak will allow fresh air to enter the system on the negative pressure side of an exhaust event, this will cause an oxygen sensor to produce a lean reading. An exhaust system manages both pressure and vacuum cycles while an engine runs.
What to do if your lean code is incorrect?
Using sensor safe carburetor cleaner to clean this filament can sometimes remove these deposits allowing the sensor to obtain a correct reading. Step 6 – Testing the exhaust system oxygen sensors can help determine the functionality of the sensor. If the sensing element fails, feedback information will be incorrect causing a lean mixture code.
What are the symptoms of lean idle on a motorcycle?
Spark plugs are clean – No residue. Insulator may be white. Runs better at higher altitudes – AFR becomes normalized due to reduced atmospheric pressure allowing fuel into the venturi easier. Backfires – Popping on deceleration for a lean idle circuit or backfires in general.
How does a PCM diagnose a lean running engine?
Lookup tables in the PCM retrieve a base injector on-time command. This base command is then modified as needed based on inputs such as engine speed, barometric pressure, engine coolant temperature and TPS and its rate of change. The result becomes the injector pulse width command, which is then fed forward to the injector.
What are the symptoms of a lean running engine?
A lean running condition may manifest in driveability symptoms that have not (or not yet) triggered a DTC. Customer complaints may include symptoms such as decreased fuel economy, lack of power, hesitation on acceleration, backfiring through the intake, overheating, weird smells or other problems.
Using sensor safe carburetor cleaner to clean this filament can sometimes remove these deposits allowing the sensor to obtain a correct reading. Step 6 – Testing the exhaust system oxygen sensors can help determine the functionality of the sensor. If the sensing element fails, feedback information will be incorrect causing a lean mixture code.
What are the signs of a failing ECU?
Common signs of a failing PCM/ECM/ECU include the Check Engine Light coming on, engine performance issues, and the car not starting. 1. Check Engine Light Turns On