Before you get too carried away, charge the battery for at least an hour on low charge, then measure the voltage. I'll bet you'll find less than 11.0 volts. Bad battery, engine computer lost its memory, engine won't idle unless you hold your foot on the gas pedal; about 1/4".
If it runs as long as you hold the gas pedal down a little, all you have to do is relearn minimum throttle. That must be done anytime the battery is disconnected or run dead. Until you do this, the engine computer won't know when it must be in control of idle speed.
To relearn minimum throttle, drive at highway speed, then coast for at least seven seconds without touching the brake or gas pedals. The computer will memorize the voltage from the throttle position sensor. After that, whenever it sees that same voltage, it knows it must control idle speed.
Fuel trim data must also be relearned while you drive under varying conditions. During the few minutes that takes, it might not run the best.
The relay you hear clicking in the dash is due to low battery voltage. With a dead cell in the battery, some of the computers won't turn off so they drain the battery. If you find at least 12.5 volts after charging the battery, then it might be necessary to look for a drain or a charging system problem.
Thursday, April 16th, 2009 AT 12:42 AM