My SHO won't start - What's the deal?
Thanks to George Fourchy:
Symptom
You're driving along, and suddenly the engine quits for a second, and the CE light comes on, then everything is OK. Or, you go over a bump, and the engine quits instantly, and the CE light comes on. You pull over and try to start again. The engine cranks over fine, but there isn't a pop. You have heard stories of the crank position sensor, the one buried under the water pump, causing the engine to quit if there is a coolant leak that is keeping it soggy. You holler and scream, just knowing you are looking at either a huge expense, or a lot of work, or both. And, if you are a long way from home, you are really mad.
Possible Solution
First, how bright is the CE light when it is on with the key on and engine off? Is it as bright as the "ABS" light? Or is it dimmer than that? When you turn on the key, do you hear the whine of the fuel pump? If you are home or near friends with tools, do you get a spark from a timing light after you connect it to a plug wire and the battery? Do you hear the fuel pump when the key is turned to the run position?
If you don't get a spark, or if you do have an operating fuel pump and good pressure, the chances just went way up that it is in fact the crank sensor, or CKP. But, if you do get a spark, your fix might be very easy.
Are your battery cables original, or have the ends been replaced with the cheap ones you can get everywhere with two small bolts that clamp the bare end of the cables to the lead of the connector? If you have these cheap connectors, how secure is the small wire that comes off the positive cable that powers the computer? And the negative one?
Check for spark: hook an inductive timing light up to a plug wire and crank the engine over with the key. If the CKP is OK, you usually will have spark, whether the computer is powered or not. (A failed coil pack and/or DIS module can also cause no spark, but these conditions are much less common than bad battery cables.) If you do not hear the fuel pump coming on when the key first comes on, and the CE light is dimmer than normal (this is the big clue), the computer is very likely un-powered, and there is no way the engine will run if it is. The fuel pump will not be supplying pressure, and the injectors think you are inside your house. I have a '91 Plus (the "Plus from Hell") that had that problem while being driven all the way across the country, from Florida to California.
Tighten those two bolts down tight that hold the cable into the connector, and as soon as you can, replace them with integral cable/connectors (new cables). Corrosion and looseness will cause the small wire to become poorly connected to the connector, even though it is nestled next to the big cable, and the car will die. It cost me $5000 to figure that out, what with renting cars to drive home, driving back and towing the Plus home, and lodging for an extra week or 10 days. That's not something I'd want to do again, and I'd sure like to prevent someone else from having the same problem, considering the fix is so simple.
The permanent solution is to remove the cheap terminal from the battery, and either replace the cables with new factory cables, or use good aftermarket cables that have soldered or otherwise permanently sealed battery connectors, to prevent any possibility of the power lead to the computer being loose and corroded. You can cut the factory lead back a ways from the push-connector that is adjacent to the positive connector, and solder it to the new small wire that comes off the new cable If you feel confident in your soldering technique, you can purchase a short positive cable with the pigtail for the computer, and solder it to the original cable, just replacing the end, rather than the whole cable. An inexpensive, simple fix for a potentially very serious and expensive problem.
