How do you replace the mass air flow sensor in a 2003 Honda crv?

Answer 1

There are TWO Oxygen sensors. One is located just in front of the catalytic converter, either on the exhaust manifold, or on the inlet area of the catalytic converter itself. The second one is located either at the exhaust end of the catalytic converter, or in the exhaust pipe directly after it. (CAUTION: The electrical wires are permanently connected to the sensor and must not be removed from it, or it will be destroyed. Due to the constant changing temperatures to which they are subjected they may be DIFFICULT to remove.) (NOTE: There is a special tool designed for their removel - use of an open end wrench may round off the hex head.) Start and run the engine for a minute or two (to slightly expand the metal of the exhaust system). Disconnect the cables(s) from the battery, and then, using caution not to burn yourself, carefully remove the sensors from their seat. Disconnect the sensors electrical connector. CAREFULLY unscrew the sensor. (If you are inserting a new sensor - the threads should already be coated with anti-seize compound. If you are re-using the old one MAKE CERTAIN that you apply anti-seize compound or it will be virtually impossible to remove it the next time.) Install the new sensor, tightening it securely, re-connecting the leads to the wiring harness, and making sure the protective boot is in the proper position. Re-connect the battery - test drive the vehicle to make sure the trouble code has disappeared.