1994 Taurus SHO, 3.2L, A-T, 202,000kms
A while ago the Alternator warning light would illuminate when the RPM's were below 1800.
Revving the engine to above the 1800RPM point would see the light go off, and normal operation continued even at RPM's below 1800. At times the light would not come on again, but then reappear sometimes minutes later, sometimes only the next day. At times the lightwould not go off until the revs were over 2500-3000. Semed to be geting worse.
At times in order to keep the light off, I would have to turn off the OD so that the engine speed would increase by 1000RPM's, and thus allow for the light to go off when vehicle speed was low, or in urban situations run the car in 2nd gear(A-T) so as to pick the RPM's up, and get the light out.
Today I had the alternator(Bosch replacement 20 mths ago)bench tested, and all 5 times the test was run, it came back good. I thought it may have been the internal regulator(diodes)problem. Not they said.
Re-installed the alternator, started the car, light was out, but after a while it started to flicker on and off again whilst at normal idle. As it warmed up, it took higher RPM's to get it to go off, as much as 3000.
After allowing the engine to run for a while, the ABS light came on, the Tach dropped to ZERO, the engine died. The car would not restart, as the battery was drained.
Recharging the battery has everything running normally once again. All lights out.
Note that the 6 year old battery was replaced a month ago, as it died(tested BAD).
The alternator light issue was happening before and after battery replacement as well.
Connections at battery, and alternator are solid.
Further connection checks discovered that at the starter solenoid, were the Positive battery cable is attached, is loose. Not the connection itself, but the whole gizmo to which the wires are attached. It can rotate. I don't believe this should be happening!
I suspect that there may be a bad connections within the solenoid.
Or could it be that when bench tested cold, it was good, but with once run, and thus the alternator gets warmed-up, that the diodes/etc start to fail.
Is the charging system integrated with the starter/solenoid, and possibly causing the issue, and the battery drain?
Your thoughts are appreciated! ?
Sunday, August 26th, 2007 AT 7:10 PM