'96 monte carlo with starting problems

[newguy123]

The car runs great, but from time to time, maybe once a month or every few months, it won't start for extended periods of time. A couple of days, usually, but then it will start just fine after that, and will continue to run perfectly for another couple of months. But after about three or four months, it'll start acting up again and go out of service completely for another couple of days, sometimes up to a week. I've taken it to various car technicians around my area and none of them can seem to figure out what exactly is the problem, it's just run my bill up. I was wondering if anyone else had these same problems, or any insight as to what the cause may be. Thanks in advance for any help.

[Blue Bowtie]

Welcome Aboard!

When the no-start condition occurs, does the starter crank the engine? Does the fuel pump run its prime cycle when the ignition is first turned on? Is there spark?

You'll need to get in a pattern of starting the vehicle EVERY time so that when it doesn't start, you'll be able to report the differences.

Begin by closing the door and turning off the radio and all the accessories (like the heater fan) so you can hear.

1. Insert the key and turn it to the RUN position only. Do not attempt to start the engine. When you first turn the ignition on, the "Service Engine" lamp should turn on briefly (about ¼ second), then turn off briefly (about ¼ second), then turn back on and remain on until the engine is started or the ignition is turned off.

2. While the ignition is turned on, you should be able to hear the electric fuel pump in the tank run for a two-second prime cycle. If the pump does not run, there will be no starting fuel.

3. When the ignition is turned on, the "Security" lamp should also turn on. The lamp should remain on for about five-seven seconds. If the lamp flashes instead of steady illumination, the BCM is indicating that it does not recognize the resistor pellet in the ignition key,and will not allow the engine to start. If the lamp remains lit for more than ten seconds, the system may have lost connection with the key during the last drive cycle, and it may be in lockout.

4. While cranking the engine (engaging the starter) the temperature gauge should begin to sweep all the way toward the full hot end of the scale. The warning lamps on the instrument cluster should all illuminate EXCEPT the security lamp. If some do not, they may only be burned out, or there may be an ignition switch problem.

5. If the engine does not crank (starter will not operate) but the "Security" lamp is not flashing, there may be a problem with the Park/Neutral safety switch. If everything else operates normally, try starting the engine with the transmission in Neutral.