I’ve been chasing two no-start conditions for some time. The subject of this article is my 2002 Ford Taurus… and it is very much frustrating me. Electrical gremlins are some of the worst car problems. Take this ground problem to the right, for instance. Is it a problem? What uses this ground? Is it grounding properly or not?
I don’t have those answers, but it turns out this was not the problem.
If you have a problem with your brakes, it’s pretty obvious. They squeal. Or there isn’t enough material left. Or maybe you just don’t stop (that is very frightening). Both my wife and I have experienced the “pedal to the floor” failure of one half a vehicles brake system failing. It is not a nice feeling. But the repair is straight forward; mechanical even.
The no-start issue is frustrating partially because both cars are doing it and partially because it’s a complicated system and it’s easy to screw up the diagnosis. Early on in the Taurus’ case, I managed to convince myself that the ignition switch was at fault. This is not the bit you put the key in, but a long box with a lever driven by turning the key that opens and closes many different contacts that control many different things in the car.
While combing the Taurus Car Club of America’s forums, I happend upon some diagrams posted by one of the members that came from “alldata.” Turns out alldatadiy.com gives access to car technical manuals for home users (their other main site provides this for independent auto repair shops and even provides other garage management software). I quickly subscribed for my own vehicles — the information they provide for chasing electrical problems far exceeds the information provided by Haynes manuals I’d been using previously.
I became convinced that the ignition switch was faulty because the alldata “data” was faulty on the configuration of the pinout of the starter relay. It mixed up two of the pins as I later figured out. Since buying a new ignition switch didn’t fix the problem (and was thankfully cheap), I went back to diagnosing. Somewhere in there, I managed to blow the fuse, but everything eventually led to the computer.
Now the ground near the computer was also a mess. With hope anew that I wouldn’t have to deal with the computer, I disconnected the ground, used my tap-and-die set on the screw and hole, and then used my rotary tool to shine up the lugs.
Again there was no joy. This was a real letdown as it represented the last thing that could be the problem before blaming the computer.
Turns out the Taurus is pretty special. There’s only 5 wreckers in Canada that have the computer that matches mine (where other models of computer are quite common). It would appear that my Taurus configuration matches more closely how many Sables (Mercury vehicles are only sold in the US, not Canada… since some point a number of years ago). I suppose maybe the leather seats and climate control version of the Taurus we had most closely matches a Sable — and maybe it would have been badged as such if it hadn’t headed to Canada? I dunno.
However, one large beef I have with Taurus repair: The manual should simply state: “Remove the intake plenum and then decide what to repair.” At this point I have done a number of repairs on the engine chasing a missfire issue that has ranged from noticeable to quite severe and almost anything you need to fix requires removing the intake plenum on this car. You can see (somewhat) in the picture to the right that the computer will not come out through the hole available and the item in it’s way (not really shown) is intake plenum.
I suppose it’s possible that a new computer might fix the misfire issue, too. I’m just hoping that it will at least fix the no start issue. At this point the new computer is on it’s way from Winnipeg by Greyhound, so we’ll have to wait a few days to see if we’re right.