Engine - Revised Vacuum Test Procedure

Number: 93-116-6
Sector: 6
Date: MARCH 1993
Corporate Bulletin No.: 336001
ASE No.: A1. AS

Subject:
VACUUM TEST PROCEDURE

Model and Year:
1993 GEO METRO

SERVICE UPDATE`

This bulletin replaces the 'Vacuum Test" procedure in Engine General Information and Mechanical Diagnosis (Section 6) of the 1993 Geo Metro Service Manual (ST370-93).

VACUUM TEST

1. Stan engine and allow d to reach normal operating temperature. Make sure that the engine idle speed is between 700 to 800 rpm.





2. Stop engine and install a vacuum gage between the manifold absolute pressure (MAP) sensor and the throttle body (TB).
a. Disconnect the MAP sensor vacuum hose from the TB.
b. Using a three-way vacuum hose joint and two pieces of vacuum hose, connect a vacuum gage between the MAP sensor and the TB (Figure 1).

3. Start and run engine at idle.

Measure Engine vacuum pressure. Standard vacuum pressure is 52.9 to 66.3 kPa (15.7 to 19.7 in. Hg) at 700 to 800 rpm.

4. Stop engine and remove vacuum gage, three-way joint and extra vacuum hoses.

5. Reconnect MAP sensor vacuum hose to TB.