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Obviously, replacing the MAF sensor is needed in this case.Chevy traverse no crank no start. This prevents the PCM from accurately controlling fuel, which will result in an engine that either will idle roughly or not at all. Rough idle or stallsĪ completely failed MAF sensor will not send any airflow information to the PCM. 96 4-Dr Blazer 4x4 Sasd 5.7 Vortec, 411 PCM. The mass air flow sensor is part of the engine’s intake system and is located between the air filter box and the throttle valve. Installed the new Mass Air Flow Sensor this afternoon, got out on the highway, same crap. Defective or dirty mass air flow sensor (MAF) in your Chevy TrailBlazer can result in loss of power, uneven engine running, erratic idling, misfires, poor exhaust emission values including black smoke. If the circuit has an issue, replacing the sensor will not solve your problem. Jump to Latest Follow 1 - 15 of 15 Posts. Before replacing the sensor, however, the rest of the circuit should be checked for proper operation. A MAF sensor that behaves like this will require replacement. A trained technician will have to look at fuel trim status with the use of a scan tool to verify this. If the engine control system is working correctly, you will probably never notice this except for a change in fuel economy. Constantly runs rich or leanĪ MAF sensor that continuously over-reports or under-reports airflow into the engine will cause an engine to run rich or lean. The fix is as simple as cleaning the MAF sensor with an approved cleaner, which the technicians at YourMechanic can do for you if they determine that this is the root problem. Anything that acts like insulation to the hot wire will cause this type of issue.
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What happens is the system was likely reset because of the battery being remove. This is a common issue on the 4.2L engine. No, your engine does not use a Mass Air Flow sensor (MAF), it only has a Manifold Absolute Pressure (MAP). The contamination can come in the form of spider webs, potting compound from the MAF sensor itself, dirt that gets attached to oil on the MAF from an over-oiled aftermarket air filter, and more. Location of the MAF sensor on a 2004 trailblazer. These symptoms indicate a MAF that has a contaminated hot wire. There are a number of driveability issues that arise from faulty MAF sensors. This equates to more air into the engine or less air into the engine. Whenever the temperature difference between the two sensing wires changes, the MAF will either increase or decrease the current to the heated wire.
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The microprocessor (computer) inside the MAF determines the amount of air entering the engine by how much current is required to keep the hot wire about 200 ℉ hotter than the cold wire. There are several designs of MAF sensors, but the most common by far is the hot wire MAF sensor. The PCM uses this input to calculate engine load.
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Mass Airflow Sensors (MAF) have the responsibility of reporting the amount of air entering the engine to the Powertrain Control Module (PCM).
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