help car idles like shit.
#1
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having idle issues it seems like the iac isn't fast enough to save the car from dying it tries and sometimes it saves it. i replaced the iac and now it is worse i know it has to learn its position but it seems like it is having trouble doing it. i have had the battery disconected berore and it never had problems i am starting to get really frusterated. it runs great off idle. and now when i push the clutch in it drops down streight to idle and it use to stay up and go down as the car slowed down. has anyone had these problems before.
#2
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did you install it correctly? not saying you didnt! here ya go! just in case!
TESTING
See Figure 1
Visually check the connector, making sure it is connected properly and all of the terminals are straight, tight and free of corrosion.
Unplug the IAC connector and check resistance between the IAC terminals. Resistance between terminals A to B and terminals C to D should be 40-80 ohms. If resistance is not within specification, the IAC valve must be replaced.
Fig. 1: Idle Air Control (IAC) valve circuit
Check resistance between the IAC terminals A to C, A to D, B to C and B to D. Resistance should be infinite. If not, the IAC valve is faulty.
If the resistance is within specification, check the IAC circuits back to the PCM for continuity.
If the valve and circuits are functional, the computer control module may be faulty.
REMOVAL & INSTALLATION
See Figures 2, 3, 4, 5 and 6
On some models it may be necessary to remove the air inlet assembly.
Disconnect the negative battery cable.
Detach the IAC valve electrical connector.
Fig. 2: Detach the IAC valve electrical connector
Remove the IAC valve by performing the following:
On thread-mounted units, use a 11/4 in. (32mm) wrench.
On flange-mounted units, remove the mounting screw assemblies.
Fig. 3: After removing the mounting screws, remove the IAC valve
Remove the IAC valve, then remove the and discard the IAC valve gasket or O-ring.
Fig. 4: Unfasten the retaining screw, then remove the IAC valve from the throttle body
Fig. 5: Exploded view of the throttle body (1), IAC retaining screws (4), IAC valve (3) and O-ring (2)
To install:
Clean the mounting surfaces by performing the following:
WARNING
NEVER soak the IAC valve in any liquid cleaner or solvent!
If servicing a thread-mounted valve, remove the old gasket material from the surface of the throttle body to ensure proper sealing of the new gasket.
If servicing a flange-mounted valve, clean the IAC valve surfaces on the throttle body to assure proper seal of the new O-ring and contact of the IAC valve flange.
If installing a new IAC valve, measure the distance between the tip of the IAC valve pintle and the mounting flange. If the distance is greater than 1.102 in. (28mm), use finger pressure to slowly retract the pintle. The force required to retract the pintle of a new valve will not cause damage to the valve. If reinstalling the original IAC valve, do not attempt to adjust the pintle in this manner.
Fig. 6: If installing a new IAC valve, measure the distance of the pintle extension (1)
Install the IAC valve into the throttle body by performing the following:
With thread-mounted valves, install with a new gasket. Using a 11/4 in. (32mm) wrench, tighten to 13 ft. lbs. (18 Nm).
With flange-mounted valves, lubricate a new O-ring with transmission fluid and install on the IAC valve. Install the IAC valve to the throttle body. Install the mounting screws using a suitable thread locking compound. Tighten to 28 inch lbs. (3.2 Nm).
Attach the IAC valve electrical connector.
Connect the negative battery cable.
No physical adjustment of the IAC valve assembly is required after installation. Reset the IAC valve pintle position by performing the following:
Depress the accelerator pedal slightly.
Start the engine and run for 5 seconds.
Turn the ignition switch to the OFF position for 10 seconds.
Restart the engine and check for proper idle operation.
TESTING
See Figure 1
Visually check the connector, making sure it is connected properly and all of the terminals are straight, tight and free of corrosion.
Unplug the IAC connector and check resistance between the IAC terminals. Resistance between terminals A to B and terminals C to D should be 40-80 ohms. If resistance is not within specification, the IAC valve must be replaced.
Fig. 1: Idle Air Control (IAC) valve circuit
Check resistance between the IAC terminals A to C, A to D, B to C and B to D. Resistance should be infinite. If not, the IAC valve is faulty.
If the resistance is within specification, check the IAC circuits back to the PCM for continuity.
If the valve and circuits are functional, the computer control module may be faulty.
REMOVAL & INSTALLATION
See Figures 2, 3, 4, 5 and 6
On some models it may be necessary to remove the air inlet assembly.
Disconnect the negative battery cable.
Detach the IAC valve electrical connector.
Fig. 2: Detach the IAC valve electrical connector
Remove the IAC valve by performing the following:
On thread-mounted units, use a 11/4 in. (32mm) wrench.
On flange-mounted units, remove the mounting screw assemblies.
Fig. 3: After removing the mounting screws, remove the IAC valve
Remove the IAC valve, then remove the and discard the IAC valve gasket or O-ring.
Fig. 4: Unfasten the retaining screw, then remove the IAC valve from the throttle body
Fig. 5: Exploded view of the throttle body (1), IAC retaining screws (4), IAC valve (3) and O-ring (2)
To install:
Clean the mounting surfaces by performing the following:
WARNING
NEVER soak the IAC valve in any liquid cleaner or solvent!
If servicing a thread-mounted valve, remove the old gasket material from the surface of the throttle body to ensure proper sealing of the new gasket.
If servicing a flange-mounted valve, clean the IAC valve surfaces on the throttle body to assure proper seal of the new O-ring and contact of the IAC valve flange.
If installing a new IAC valve, measure the distance between the tip of the IAC valve pintle and the mounting flange. If the distance is greater than 1.102 in. (28mm), use finger pressure to slowly retract the pintle. The force required to retract the pintle of a new valve will not cause damage to the valve. If reinstalling the original IAC valve, do not attempt to adjust the pintle in this manner.
Fig. 6: If installing a new IAC valve, measure the distance of the pintle extension (1)
Install the IAC valve into the throttle body by performing the following:
With thread-mounted valves, install with a new gasket. Using a 11/4 in. (32mm) wrench, tighten to 13 ft. lbs. (18 Nm).
With flange-mounted valves, lubricate a new O-ring with transmission fluid and install on the IAC valve. Install the IAC valve to the throttle body. Install the mounting screws using a suitable thread locking compound. Tighten to 28 inch lbs. (3.2 Nm).
Attach the IAC valve electrical connector.
Connect the negative battery cable.
No physical adjustment of the IAC valve assembly is required after installation. Reset the IAC valve pintle position by performing the following:
Depress the accelerator pedal slightly.
Start the engine and run for 5 seconds.
Turn the ignition switch to the OFF position for 10 seconds.
Restart the engine and check for proper idle operation.
#3
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wow thanks i started it the other day and it seemed to be running like it use to so it may have fixed it i think it was just having a hard time learning it with a cam.