Air Intake System — Throttle Control System (Troubleshooting Flowchart, cont'd)
6-87flowchartBranches differ for With CATA (4P connector) vs Without CATA (2P connector).
1
(From page 6-86)
2
Warm up engine to normal operating temperature (cooling fan comes on).
3
Check for vacuum at #22 vacuum hose.
4
Is there vacuum?
YES
Throttle control system is OK.
NO
5
Disconnect the 2P (Without CATA) or 4P (With CATA) connector.
6
Is there vacuum?
NO
Replace the dashpot control solenoid valve.
YES
7
Turn the ignition switch OFF.
8
Disconnect "B" connector from ECU.
9
Check for continuity to ground in the BLU (to ECU, B2) wire.
10
Is there continuity to ground?
NO
Subsitute a known-good ECU and recheck. If symptom goes away, replace the original ECU.
YES
11
Repair short to ground at BLU wire between ECU (B2) and the connector.