Diagnosis & Repair

Connect scan tester to DLC3 connector. See Figure. Turn ignition on. Turn scan tester on. Using scan tester read MAP sensor value. If reading is same as atmospheric pressure, go to next step. If reading in not same as atmospheric pressure, inspect component and ECM connections. Problem is intermittent.

Fig 1: Connecting Scan Tester Locating DLC No. 3 (DLC3)
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Access ECM behind glove box. Turn ignition on. Backprobe ECM connector. On A/T models, measure voltage between terminals No. 1 (Light Green/Red wire) and No. 9 (Brown wire) at ECM E6 connector. On M/T models, measure voltage between terminals No. 18 (Light Green/Red wire) and No. 16 (Brown wire) at ECM E4 connector. See Fig 1. On all models, if voltage is 4.5-5.5 volts, go to next step. If voltage is not 4.5-5.5 volts, replace ECM and retest.
Backprobe ECM connector. On A/T models, measure voltage between terminals No. 2 (Pink wire) and No. 9 (Brown wire) at ECM E6 connector. On M/T models, measure voltage between terminals No. 4 (Pink wire) and No. 16 (Brown wire) at ECM E4 connector. On all models, if voltage is 3.3-3.9 volts, replace ECM and retest. If voltage is not 3.3-3.9 volts, go to next step.
Check for an open or short circuit between MAP sensor and ECM. See appropriate wiring diagram in WIRING DIAGRAMS article. Repair as necessary. If circuit is okay, replace MAP sensor and retest.

Fig 2: Engine Control Module (ECM) Connector Terminal ID - A/T

Fig 3: Engine Control Module (ECM) Connector Terminal ID - M/T