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Check Idle Air Control Valve (IACV) Housing

1. Remove IACV multiplug.

2. Remove bolts securing IACV housing to plenum.

3. Remove gasket and discard.





4. Examine aperture on housing (figure 2). Faulty castings have an aperture of approximately 8 x 3 mm. (5/16 x 1/8 in.). Normal aperture should be 11 x 11 mm. (7/16 x 7/16 in.).

5. Corners marked in illustration are square on faulty castings (normally they should be slightly rounded).

6. On good castings, the IACV spring is clearly visible but more difficult to see on faulty castings.

7. If the casting is normal, reinstall casting on IACV with new gasket.

8. If casting is faulty, remove IACV from housing and file down housing aperture to meet specification as outlined above.