joshmck

99 Malibu 2.4L engine. It starts, runs for a second or 2, then dies. No dash lights or exterior lights come on when it does start and the gauges on the dash don't move. After this happens, it will either fire right back up and do the same thing again or it will just crank but not fire. Some research has led me to believe it's the ignition switch. Posting on here either for confirmation or to be pointed in another direction if necessary. Thanks

EinST

In the driver side I/P fuse block, check the voltage at the TURN LPS fuse against a good ground with key on, engine off (red probe into the hole on the fuse, block probe on something that screws into the chassis). Now, do the same for the IPC/BFC ACC fuse and PCM ACC fuse. The TURN LPS fuse is on one leg and the other two fuses are on another leg of the ignition switch. Good voltage on both legs are required for powertrain functions.

joshmck

So I assume bad voltage on one or all legs indicates bad ignition switch? What should the voltage be? I'm guessing somewhere in the 12's but not sure. Not very good with electrical, but would really like to try to diagnose and fix this without going to a shop. Thanks

EinST

There all should be close to the battery voltage with key on. If not, remove the electrical connectors from the ignition switch and then measure the supply voltage on the red wires. Again, good voltage is as close to the battery voltage. If the ignition switch is getting good supply and passing on lousy voltages, replace the switch.

joshmck

Battery voltage is at 12, slightly below where it ideally should be. It's a pretty old battery, so I'll be replacing it. All of the fuses were close to the same voltage and the ignition switch also checked out fine. Battery voltage with engine running is around 14, indicating good charge from alternator. Still gonna have alternator checked. Not sure what else to try if it isn't the battery

EinST

Hmm, you now say "with engine running" but you made it sound like it won't stay running in your first post. Let's start over. Is this an intermittent problem and, if so, how intermittent? When the issue arises, what do you see in the I/P cluster? Do the gauges and warning indicators acts normal, i.e., go through the bulb test with key on? Does the CEL stay on? What else? What does the THEFT SYSTEM indicator do before and after the key is turned to START (again, when the issue arises)?

joshmck

It is an intermittent problem. Sorry if i didn't make that clear. When the issue arises, nothing at all lights up on the dash. When i was working on it Tuesday, I didn't have any issue at all with keeping it running. Every time i tried it, it started and ran fine, which caused me even more confusion. The problem first arose Monday evening but after several tries, it finally started and ran like normal. Tuesday morning,i couldn't get it to stay running at all. Again, when the problem occurs, the engine will crank no longer than it normally does when everything is working fine, fire, and shut off after a second or two and there is absolutely no activity from the instrument panel, warning lights, or gauges. Also, sometimes but not every time it will just crank and not refire after it dies. Hope this clears up the confusion. Appreciate your help.

EinST

Your original question was if it could be the ignition switch. The next time it exhibits the symptom as described, measure the voltages downstream of the ignition switch as in my post #2. Then, in the underhood fuse block, measure the voltages at IGN SW BATT1 fuse and IGN SW BATT2 fuse that are upstream of the ignition switch. That should tell you whether or not the ignition switch could be the culprit.