Honda Civic/Acura Integra

since 1994 of release

Repair and car operation

System of stabilization of turns of idling – the general information, check of a condition and IAC valve replacement

General information

When the engine works at single turns, the structure of an air and fuel mix is supervised by system of stabilization of turns of idling (IAC). On the Civic models the system consists of RSM and the IAC valve, on the Integra models – from RSM, the thermosensitive valve of turns of fast idling (FIT) and the IAC valve. Activation of the IAC valve is made at the command of ESM/RSM, depending on the current load of the engine (turning on of the conditioner of air, power steering use, unit temperature etc.) . the valve regulates size of the air stream submitted to the inlet pipeline bypassing a butterfly valve. Basic data ESM/RSM receives from VSS sensors, eats, PSP sensors switches and operation of the coupling of coupling of the К/В compressor. Depending on the current load of the engine the module as appropriate corrects turns of its idling. In order to avoid violation of stability of turns of idling at engine start the IAC valve opens at the moment of a provorachivaniye and remains open for some time right after start, providing supply of additional air in the inlet pipeline.

Check

PERFORMANCE ORDER

1. Cock the parking brake, prop up car wheels protivootkatny boots and transfer transmission to neutral transfer (RKPP) or to the situation "R" (AT). According to instructions of manufacturers connect to the engine a tachometer. Start the engine and lift frequency of its rotation to value of 3000 rpm. Wait operations of the fan of system of cooling, then dump turns to single and disunite the electric socket of the IAC valve. Try not to touch fan blades with hands and not to allow hit in contact with them of hair and free elements of clothes. At a detachment of the valve there should be an appreciable decrease in turns of the engine, otherwise the valve most likely is faulty. If falling of turns takes place, and the problem with a podderzhivaniye of their stability does not disappear, check a condition of a plait of electroconducting and its contact connections on a site between the IAC valve and ESM/RSM. 2a. Disconnect electroconducting from the IAC valve, include ignition (do not start the engine) and measure tension between the positive plug of the socket from a plait (the plug of a yellow-black wire) and mass of a body (see accompanying illustrations): Civic models. The voltmeter should register tension of the battery. If tension is absent, check a condition of a yellow-black wire of electroconducting on a site between the IAC valve and the main PGM-FI relay. In any case leave the socket disunited for performance of further checks. 2b. Integra model valve. 3. If the plait of electroconducting of IAC consists of two wires, connect the valve by means of two wires crossing points directly to the battery (the black and yellow wire is connected to the positive plug, to the negative – black-dark blue). The valve should publish click each time when giving food. Do not hold the valve zapitanny more long than it is necessary to catch click! 4. If the plait consists of three wires, connect negative щуп an ohmmeter to the central plug of the socket, and positive – serially to each of lateral. In both cases the device should register resistance 16÷28 Ohm. 5. At positive results of the checks stated in paragraphs 3 and 4 the car it is necessary to drive away on car repair shop for more detailed diagnostics of condition ESM/RSM and an IAC valve contour.

Replacement

PERFORMANCE ORDER

1. Disconnect from the IAC valve electroconducting. 2. Turn out two fixing screws and remove the sensor from the delivery chamber of an air path (see illustrations above). 3. Installation is made upside-down. Do not forget to replace a sealing ring.