Howdy all. I was on a 200 mile road trip last night. As I was driving, I thought i saw the headlights get brighter. I drove about 20 miles and noticed that the headlights would get dim for a while then get bright again. About 140 miles into the drive, the headlights were dimming and finally the air bag light came on and about 5 minutes after that the overdrive light came on and kicked out of overdrive, a short time later, the car started to lose power. I pulled to the side of the road and thought to limp it along till it dies completely. I figured that I lost the alternator and was running on battery voltage, even though I did not get any indicator light. As I was slowing down, the lights became bright and I had power again. I drove another 10 miles and the lights started to dim again. I pulled into a truck stop that was near by and parked. after I came out of the store, I started it back up. It barely started and acted like a weak battery. i had my multi-meter with me and checked the voltage on the battery. It was 13.1 volts at idle and when I reved the motor a bit it jumped up to 13.6 volts. I made it to my destination and it seems to be running now. I am thinking that I might have a bad cable or ground. The battery terminals are clean and the cables at that end look good. Does the battery light indicate an alternator failure or low battery voltage, because it never came on. Anybody have any ideas where to start? Thanks in advance for any help. Tom

 

a bad alternator can make lights act up, if it was 13.1 volts at idle youre not charging enough. should be 13.9-14.5 volts.

 

Do u have a chech engine light. If u do check for codes. It could be maf or a sensor of some sort.

 

There were no codes when I hooked up my scan tool. Maybe I should buy an alternator and belt for the drive back.

 

Almost assuredly an alternator problem. Mine just did the same thing; never died completely so I did not get the battery light, but stopped keeping the battery charged up. Measured about 13.1 volts when engine running, which is way too low. Replaced the alternator and now measure about 14.4 volts when engine running. It's a moderately difficult job; I disconnected/removed the radiator fan assembly and unbolted the radiator (but did not disconnect the hoses) so i could move it to the side. Needed to do this to provide enough room to move the AC compressor (again, without disconnecting the refrigerent lines) out of the way. Alternator comes out the bottom. A lift makes the job easier, but it can be done on the ground. Good luck.

 

Check the battery connections, negative battery cable connections under the battery tray, and on the engine block. Check the red connectors on the battery positive post, they supply juice to the entire car.