No Change In Map From Start To Run (DTC 13)

NOTE: For connector terminal ID, see CONNECTOR IDENTIFICATION. For wiring diagram, see WIRING DIAGRAMS - 3.3L article in ENGINE PERFORMANCE. After each repair, perform TEST VER-2 .

Turn ignition on (engine off). Using scan tool, erase trouble codes. Start engine. Allow engine to run for 30 seconds. Using scan tool, read trouble codes. If scan tool does not display NO CHANGE IN MAP FROM START TO RUN, go to step 3). If scan tool displays NO CHANGE IN MAP FROM START TO RUN, go to next step.
Turn ignition off. Disconnect MAP sensor connector. Turn ignition on (engine off). Using scan tool in voltmeter mode, check voltage on MAP sensor connector terminal No. 3 (Violet/White wire). If voltage is less than 4.5 volts, repair Violet/White wire as necessary. If voltage is more than 4.5 volts, replace MAP sensor.
If scan tool does not display NO CHANGE IN MAP FROM START TO RUN in step 1), start engine. Using scan tool, set engine speed to 1500 RPM. With engine speed at 1500 RPM, read MAP sensor voltage. Go to next step.
Wiggle MAP sensor connector and harness while observing scan tool display. If engine stalls or MAP sensor voltage becomes erratic when MAP sensor connector and harness are wiggled, repair harness or connector that caused the voltage change. If engine does not stall and MAP sensor voltage does not become erratic when MAP sensor connector and harness are wiggled, go to next step.
Using scan tool, read MAP sensor vacuum. While observing scan tool display, snap throttle open and closed. If vacuum does not drop rapidly to zero in. Hg, go to step 7). If vacuum drops rapidly to zero in. Hg, go to next step.
At this time, the condition required to set the trouble code is not present. 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 start up. Possible causes are: restricted or leaking vacuum/pressure to MAP sensor, ice in sensor or passage, or MAP sensor failure.
If vacuum does not drop rapidly to zero in. Hg, in step 5), remove MAP sensor and check for restriction. If a restriction is present, remove restriction and reinstall MAP sensor. If restriction is not present, replace MAP sensor.