2000 2.7 Dodge Intrepid 190k. Driving down the expressway yesterday I noticed the engine light was flashing at me. I pulled over and did a code check....nothing. I let it run for a few, and resumed my heading. It seems to cycle 4-5 flashes and then go off for a while.It never gave me any problems other then light comming on and off. This morning I drove it to work andthe light didn't come on once.Still no codes. Any suggestions?

 

The first thing I'd do is test the "test circuit" by unplugging a sensor such as an O2 or the TPS (nothing like the ignition coil though as that could cause damage). Crank the car, and see if it not only comes on, but stores the code. Hook it back up, and the code sohuld remain. It should stay in memory for 30 trip cycles (which is a key start with the engine hot). You need not test how many trip cycles it stays on, only that it holds the code in memory after the fault is gone.

The reason for all of this is the PCM could be bad. It drives the light and holds the codes. It may be a wire shorting out making the light blink, or the PCM test circuit is bad. Also most OBDII scan tools have the ability to test the light, but this only ensures the light can come on.

Try it and let me know what happens.

PS to reset the light after the inducd fault, either use a scan tool, or disconnect the battery for about 15 min. I always use the tool and am not exactly sure about the lenght of time to have the battery off. I have heard 10 min, but I'd do 15-30 if the ten is too short.

 

All it takes is 5 minutes to discharge the PCM.

 

Flashing MIL usually indicates a cat damaging misfire. If you're not feeling it, there could be a problem with the crank or cam sensor that makes the PCM think there's a severe misfire.