2003 Sable Electrical problems - Ford Forums

Ustacould · 07-06-2008, 19:30

I have a 2003 Sable with the 3.0 liter DOHC. While driving on the highway and running either A/C or heater at max fan with Radio on, the car engine will die or stall violently jerking the car with all warning lights on and then continue OK. This happens at random but semi-frequent intervals. The more electronics I turn off, the less it happens but it happens all the same. No error codes or engine lights are displayed after the fact. (In one instance, it also seemed to make the AC over heat.) The radio will also turn on and off and automatically change volume as a forewarning to the sudden stall on the highway. (It has also stalled and died under similar conditions at slow speeds.) (Any suggestions will be greatly appreciated, thanks in advance.)

SHOZ123 · 07-08-2008, 13:18

Your alternator is dieing.

mre_power · 07-08-2008, 19:34

i dunno every thing should runn off of the battery till it runs out of juice. i do know that duratecs are prone to ac lock ups . this one maybe starting to go.

SHOZ123 · 07-09-2008, 01:06

The PCM relay is dropping out due to low voltage and rebooting itself when the load is gone. This is what is causing the warning lights to come on like you just turned the key on.

The battery voltage is being dragged down to under 11V.

Ustacould · 07-09-2008, 21:19

Do you think that would be caused by a weak regulator in the Alternator or the Transmission Position Sensor? From what I've been reading it seems fairly common to have the TPS in these cars cause strange issues. The regulator is something that I thought of because one of the other symptoms is when its about to happen, if I'm sitting still the speedometer needle will start to bounce.

I would have also thought that if it were a weak or bad regulator that it would happen on a much more consistent basis. I will try a test of turning everything on to see what happens and if I can find a trigger. It has seemed to come with heating or extended drives which is one reason I thought of the TPS, thinking maybe it is getting hot and sending bad messages to the control module. Thanks for the feedback so far.

SHOZ123 · 07-13-2008, 12:39

Where the alt is on the Duratec it is such a PITA to get to that I would just take it out and go get a lifetime guaranteed one. The regulator may be the problem but changing out the alternator is not a simple 20 minute job.