Need Advice.....Alternator?

[gizahuna]

I'm a bit stumped on this issue.

Last Monday, my 09 4runner with 304,000 miles on it died while driving to work. All the lights started coming on and the car was losing power and bucking forward for about 20 seconds and then died. Nothing when I turned the key. I knew the battery was fine, as I just replaced it last year, so I assumed that it was the alternator.

I had it towed to my home and the tow truck driver tried to start it, but no luck. I tried when I got home...same thing. It sat all week.

Today, for laughs, I tried to start it, and wouldn't you know... it started like a charm. I put it on the OBDII scanner and all clear.

Any advice would be helpful.

 

[88Center]

Check all these and report back.

https://www.youtube.com/watch?v=9GLa7yBWJCo

 

[gizahuna]

Thanks....I watched those as well. In the past, when alternators went bad, the car wouldn't start. I've never experienced a situation where the car started back up again like nothing was wrong. Is that normal?

 

[AuSeeker]

Thanks....I watched those as well. In the past, when alternators went bad, the car wouldn't start. I've never experienced a situation where the car started back up again like nothing was wrong. Is that normal?

A car with a bad alternator and good battery will start everytime, not sure where you got the info that one would not, I've been working on all types of vehicles for well over 50+ years and never had that issue!

 

[Cezar]

Battery sits a few days, weather warms up. Car starts easy. Many such cases.

You need to put a meter on and see the alternator output.

 

[MikeinNH67]

First thing I'd look at is the battery terminals. For this sort of thing, watching the interior lights is a huge help.

1)Door open or map light on, is the light bright when not starting. If not then dead battery or terminal issue

2)Does the light dim or go out when turning the key (very slight dim ok). Weak/dead battery or terminal issue. Watch voltage on the battery posts with volt meter, should not drop much under 12v when starting or headlights on. If it maintains voltage but lights go out, clean mating surfaces of battery terminals.

3)If lights go out on #2, then come back on, that is generally a dirty terminal. It amazes me how many batteries get replaced with no cleaning of the terminals leading to future problems.

 

[gizahuna]

I put a meter on the battery terminals and both the battery and the alternator checked out great. Any other ideas?

 

[AuSeeker]

Sometimes simply using a multi-meter is not enough to find the issue, as mentioned in the posted video, take it to your local auto parts store and they will test both the battery and charging system with a proper tester, which puts a load on the system!

Also I would clean redo all body and engine grounds to ensure a proper connection.