nsavitamin.blogg.se - Efilive 7.5 vs 8.2

If the sensor in your vehicle uses a vacuum hose, it's a good idea to replace it along with the sensor.įirst, locate the sensor. Regardless, the following procedure will help you replace the sensor. With vacuum applied, the sensor should drop to about 100 hertz.Ĭonsult your vehicle repair manual for specifications.Without vacuum applied, the sensor should have about 160 hertz.Your sensor should have about the same voltage and duty cycle readings in both tests.Now, apply about 18 in-Hg of vacuum to the sensor, and note the voltage, duty cycle and frequency readings on your meter. Make a note of the voltage, duty cycle and frequency readings on your meter.Turn the ignition key to the On position but don't start the engine.Backprobe the signal and ground wires at the sensor electrical connector.

Unplug the vacuum hose form the sensor and plug in a hand-held vacuum pump to the sensor's vacuum port.

First, set your multimeter to about 100 or 200 hertz.

If your vehicle uses a digital MAP sensor, instead of an analog one, you can also test it using a DMM that can measure frequency signals. You can use an oscilloscope or a DMM with a frequency function included to test a digital MAP sensor. Your readings may vary slightly, depending on altitude and current weather conditions.

Now apply 20 in-Hg of vacuum to the sensor.

Apply 5 in-Hg of vacuum to the sensor.

Your voltage reading should be between 4.6 and 5 volts.

Turn the ignition switch to the On position, but don't start the engine.

Connect the black DMM probe to ground using any metal surface on the engine or the battery negative post.

Backprobe the signal on the electrical connector using the red DMM probe.

Connect a hand-held vacuum pump to the sensor, but don’t apply vacuum to the sensor yet.Otherwise, if the voltage rises to 5 volts, than there is a problem in the wire between the computer and sensor.If you still get a low voltage at the computer side, then you need to check the computer.You may need to measure this voltage on the same wire but at the computer side. If your voltage is lower, visually inspect the connector and wire between the sensor and the PCM for damage.The readout should show 5 volts or close to it. Set your multimeter to about 10V on the direct current (DCV) scale.īackprobe the reference wire at the connector.This will allow the computer to supply a reference voltage to the MAP sensor.