Caravan V6-201 3.3L (1995)
Throttle Body: Testing and Inspection
Minimum Air Flow Air Metering Fitting
WARNING: Apply parking brake and/or block wheels before performing any engine running test with the vehicle on the ground.
PRELIMINARY CHECK
1. With vehicle in PARK (A/T) or NEUTRAL (M/T), START the engine, turn all accessories off, and allow engine to run until the cooling fan cycles
at least once.
2. Remove intake air hose from throttle body.
3. Cover Idle Air Control by pass passage with finger.
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If engine dies, clean throttle body and retest. SEE MAINTENANCE PROCEDURES.
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If engine does not die, proceed with Minimum Air Flow Test.
TEST PROCEDURE
1. Disconnect the 3/16" idle purge hose from the throttle body nipple and cap the 3/16" nipple.
2. Disconnect PCV valve and attach metered orifice no. C-5004 (or equivalent 0.125 inch orifice) in the intake manifold PCV nipple.
3. START engine and allow to idle for at least one minute.
4. Using scan tool [1], access MINIMUM AIRFLOW IDLE SPEED TEST.
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Idle Air Control (IAC) motor should close the bypass passage fully.
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Idle spark advance should become fixed.
5. Compare idle speed on tachometer to specifications below.
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If idle rpm is within range, Minimum Air Flow is set correctly.
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If idle rpm is not within range, clean the throttle body and retest. SEE FUEL AND AIR INDUCTION/MAINTENANCE
PROCEDURES/THROTTLE BODY CLEANING.
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If throttle body has already been cleaned, and idle is not within specifications, the problem is not caused by the throttle body.
6. Shut engine OFF, remove; metered orifice, timing light and tachometer.
7. Connect PCV hose. Uncap throttle body purge nipple and connect purge hose.
Remarks:
[1] Follow scan tool manufacturer's instructions for procedures.
ODOMETER READING IDLE SPEED
Less than 1000 miles
525-875 RPM
More than 1000 miles
575-875 RPM
