Okay, I'm confused, but here is what I found. To access the sensor wires on this 3.0L engine you have to move the alternator out of the way, so I took the alternator belt completely off removed the alternator from its brackets and I hung the alternator up out of the way, leaving all the wires connected to the alternator.
I hooked up my meter on the 12v setting, connected the red meter probe to the yellow wire and grounded the black meter probe to the chassis. I set the meter so I could observe from the driver's seat. Turned key on without starting engine and meter read.765v. Started the car and meter stayed in a range of.765v to.767v. Observed meter while car ran to normal operating temperature and the range still remained in the range of.765v-.767v.
My observations were that car "did not increase" rpm's (as in the past) at startup, nor did the check engine light come on at any time. I have car off the ground and I allowed the transmission to operate at a slow speed and placed it back in park to see if rpm's would increase (as it did in the past). Rpm's did not increase then either.
The only conclusion I can initially draw is that the alternator or its wiring is causing the problem somehow.
When I replace this engine I rehooked everything as I originally found it (I take pictures to assure this). Some of the wiring to the alternator had been spliced in and is not the original wiring. I just rehooked the wires in their same positions that I saw in the pictures I took before disassembly.
Could there be a wiring screw up from an "engaged" alternator that is causing the extra voltage? Or is my present reading of.765v an indicator of something else? I see that I wrote my initial voltage finding from the yellow wire was 2.5v. I don't have an answer to why the difference now in my two voltage readings from the yellow wire. As of this moment, the voltage remains steady at around.765v.
Just to let you know. The wires to the alternator are as follows, the "male-plug" coming from the wire-harness that is from the starter side of the motor is serviced by a red and black (or dark brown) wires, the alternator "post" has two red wires to it, one coming from the wire-harness from the starter side of the motor and the other coming from the passenger's firewall wire-harness area. For a total of four wires. The wire from the alternator to the firewall side wire-harness has obviously been replaced at sometime, the rest seem original.
Also tested sensor ohms and they fell within the range found in the trouble tree chart you emailed me. Thanks for sending the chart by email, I couldn't read it on line.
Friday, September 23rd, 2011 AT 11:48 PM