Have a 1999 Concorde 3.2 that won't run right. It will usually start up and idle OK, but as soon as you touch the gas pedal it will die 80-90% of the time. Sometimes it will rev up and then start choking out at around 2k RPM, sometimes it will rev higher than that. Then after returning to idle if you touch the gas again it will die.

Trouble codes that were stored originally were 106, 300, and 1496. Since clearing the codes none have returned but the SES light is on when the engine is running at idle. I don't have a full scan tool available.

When troubleshooting the 1496 (5v low) code, I found that I only have around 1.8v on the Violet/White wire on all sensors. I have unplugged TPS, MAP, and EGR connectors without change. I'm still trying to find the A/C pressure transducer. Not sure what other sensors may run off this 5v supply (PCM connector 2 pin 61 according to the Haynes manual wiring diagrams I have).

On the PCM there are 2 large connectors (top and bottom). I'm not sure yet which connector is 1 and which is 2. However, if I unplug the bottom connector from the PCM, the voltage on the Violet/White wire on the sensors goes back to 4.9 volts.

Can anyone help me with a better location for the A/C pressure transducer? What other sensors may be running off the 5v supply? I'm hoping that one of the sensors is grounded or shorted out and it is pulling down the 5v available on the wire. Not sure why unplugging the bottom connector on the PCM brings the voltage back up but I have repeated the test several times without moving any other wiring and it seems to resolve the voltage problem, but obviously I can't run around with that connector unplugged...

 

The A/C pressure transducer is screwed on to a valve on the discharge line. The transducer can be removed or installed without evacuating the refrigerant from the A/C system