Test TC-4A - No Change In Map From Start To Run (DTC 13)

WARNING: This page is about a different car, the 1995 Dodge Pickup and 1995 Dodge Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: For circuit and connector terminal identification, see CONNECTOR IDENTIFICATION . For wiring diagrams, see WIRING DIAGRAMS section at the end of this article.

Turn ignition on with engine off. Using scan tool, read trouble codes. If scan tool displays MAP SENSOR VOLTAGE TOO LOW, go to TEST TC-5A. If scan tool does not display MAP SENSOR VOLTAGE TOO LOW, go to next step.
Using scan tool, erase trouble codes. Start engine. Allow engine to idle for 30 seconds. With engine running, use scan tool to read trouble codes. If scan tool displays NO CHANGE IN MAP FROM START TO RUN, go to step 7).
If scan tool does not display NO CHANGE IN MAP FROM START TO RUN, use scan tool to set engine speed to 1500 RPM. With engine running at 1500 RPM, read Manifold Absolute Pressure (MAP) sensor voltage on scan tool. While monitoring MAP sensor voltage, wiggle MAP sensor connector and wiring harness.
If engine stalls or MAP sensor voltage becomes erratic, inspect all related wiring and connectors. Repair as necessary. Perform TEST VER-2. If engine does not stall and MAP sensor voltage does not become erratic, snap throttle open and closed while monitoring scan tool.
If engine vacuum rapidly drops to less than one in. Hg, condition required to set trouble code is not present at this time. NO CHANGE IN MAP FROM START TO RUN trouble code sets if too small a difference is seen between barometric pressure at key on and manifold vacuum after engine start. Possible causes are: restricted or leaking vacuum/pressure hose to MAP sensor, ice in MAP sensor or passage, MAP sensor failure or PCM failure. Perform TEST VER-2.
If engine vacuum does not rapidly drop to less than one in. Hg, remove MAP sensor. Inspect MAP sensor vacuum port and vacuum connector. If restriction exists, repair as necessary. Perform TEST VER-2. If restriction does not exist, replace MAP sensor. Perform TEST VER-2.
Turn ignition on with engine off. Remove MAP sensor. Inspect MAP sensor for vacuum restriction. Repair MAP sensor as necessary. Perform TEST VER-2. If no restrictions exist, go to next step.
Using scan tool in voltmeter mode, check voltage on MAP sensor connector, 5-volt supply circuit (Violet/Black wire). If voltage is less than 4 volts, repair open Violet/Black wire. Perform TEST VER-2. If voltage is more than 4 volts, replace MAP sensor. Perform TEST VER-2.