Bad alternator?

[GangstaCowboy]

Bad alternator? Intermittent power loss at start up,not starting.

Hello-
My 2006 tahoe died about a week ago. We jumped it and drove home so I took the battery in to test at Autozone and they said it was bad. Installed new battery and ran like a champ. Today the tahoe died again, but this time a jump only got the car running for like 2 seconds. Sounds like the alternator is bad to me. I am going to take the alternator up to autozone to test. Any other suggestions? I noticed before I replaced the battery the first time that the lights would flicker at night inside the cab and the head lights would dim a little bit at random times.

 

[erikrichard]

What did the dash board volts gauge read on your way back home after getting the jump start? A battery that is discharged or close to it cannot be tested accurately, so auto zone's determination that the battery was done is in question. You could have a drain on the battery running it down, but that wouldn't explain why the truck won't run after it starts - again, you need to check the volts while running with a multimeter or just look at the gauge on the dash.

 

[GangstaCowboy]

Thanks. Ill check that tonight. We called to get it towed and tried starting it one more time and it started fine. Voltage on the dash was right under 14.

 

[GangstaCowboy]

I have never removed the belt on my Chevy vechicles. When I did this on other cars there was a belt tensioner that I could loosen. I don't seem to see one. How do I get the belt loose on this Tahoe?

 

[electro]

By turning the tensioner.

It is the left upper most pulley.

 

[DCT]

I recommend a multimeter, but your gauge is ahowing 14V. For another quick check of the alternator without removing it from the truck, get the engine running (if you can) and disconnect the battery. If alternator is bad, the engine will shut off.

I have friends who work at those parts chain stores. Every damn battery and alternator "fails".

 

[GangstaCowboy]

Thanks. I will try disconnecting the battery when I get hom to make sure. IF the car stays running is there anything else I can check? I suppose the alternator could be "failing" and that is why it runs the battery down. or there could be a drain on the battery but I wouldn't even begin to know where that would be. There are no aftermarket parts on this and I have never tinkered with wiring on it.

 

[PwtrSS_OakCliff]

On my Yukon it told me on the DIC that its not charging. Sometimes it charged and sometimes it didn't. I'm surprised your battery red light didn't come on. Make sure you take out corrosion and also check your cables and make sure they are not cut or melted also. GL

 

[GangstaCowboy]

so I disconnected my battery and the car stayed on. The voltage meter on the stayed above 14 but the lights flickered a lot. Is that normal.

 

[donut slayer]

Yes. Its normal. You need a multi-meter. Take a voltage reading before startup then after. Should be 12.6 or so off and above 14 idleing.