Voltage issues after changing starter...

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I was having intermittent starter issues for a while, and last week they became more frequent. For various reasons, I had to ensure that the car was available this week, so I decided on Friday to buy a starter locally and do the replacement over the weekend. Advance Auto Parts told me they had a Bosch rebuilt starter available. When I picked it up, I found it was a house brand rebuild of a Bosch starter. Because of my slightly dire situation, I took the AAP house brand starter instead of waiting for a better one. I'm starting to think this may have been a mistake.

On the first start after replacing the starter, the alternator whined for about a minute, and then got really loud for 10-15 seconds, and then went quiet... and then the battery light came on. The car's onboard computer showed the battery voltage between 12.00 and 12.20 volts; normally it's supposed to be between 13 and 14. I turned it off and came back to it a few minutes later, and exactly the same thing happened. The car seemed to run pretty well, so I limped it over to its second home and borrowed a car.

After having the battery checked at Pep Boys this morning and swapping out the alternator (which was a saga in its own right -- another instance of AAP calling their house brand "Bosch"), the problem persists. Different alternator, exact same noises, exact same pattern of symptoms.

I got to speak with someone who knows automotive electronics. He thinks the starter I got might have some kind of defect, or may be missing a diode that the OEM starter had. When I get a chance, I'm planning to disconnect the power cable from the starter, seal it up tightly, and roll-start the car. I figure if everything runs perfectly and the voltage reads normal, I can conclude that the starter has some kind of electrical defect and raise a big fat fuss at AAP. Comments are welcome on that plan.

Anyone have a similar experience? Any input would be appreciated.
 
Yeah, I was going to say to try and jumpstart the car with the battery disconnected. I assume there is a way to do this via jumper cables, removing the battery to starter cable, and shorting the starter with a screwdriver...

Could you have screwed up a ground someplace? That is always the first place to look. What does the drain look like, especially across the battery to starter cable, when the car is off? ignition to on position?

I find it hard to believe that even a poorly done rebuild would have omitted parts.

Let's think about the starter for a second. It consists of a solenoid (relay) and a motor, right? 12V from the ignition in on position closes the relay to give battery power directly, which spins the starter. When it is at some speed, it smartly shuts off, right?

So you have a solenoid and a line to the battery, right?

What would a stuck solenoid do? stay energized burning electricity, while the starter would disengage when spinning fast enough, right?
 
You might want to leave your battery unhooked. In case of fire, if something like the solenoid is guzzling power.
 
Originally Posted By: eljefino
You might want to leave your battery unhooked. In case of fire, if something like the solenoid is guzzling power.


I feel like the solenoid is a likely culprit too, but for a 14v alternator to drop to 12V, there has to be some pretty substantial load there... Is that viable?
 
Also, are there any other +12v feeds to the rest of the car that go off from the big lug on the starter?
 
Originally Posted By: JHZR2
Could you have screwed up a ground someplace? That is always the first place to look.

Possible, but unlikely as far as I understand.


Originally Posted By: JHZR2
What does the drain look like, especially across the battery to starter cable, when the car is off? ignition to on position?

Not sure. My volt meter is broken and I couldn't find one to borrow on short notice. All I know is that, with the engine off and the key in the "on" position, the OBC shows 12.20 volts, which is less than the Pep Boys machine showed (12.65 or something).


Originally Posted By: JHZR2
I find it hard to believe that even a poorly done rebuild would have omitted parts.

As do I. I was told it "happens all the time," but that statement is always a yellow flag...


Originally Posted By: JHZR2
Let's think about the starter for a second. It consists of a solenoid (relay) and a motor, right? 12V from the ignition in on position closes the relay to give battery power directly, which spins the starter. When it is at some speed, it smartly shuts off, right?

Sounds about right.

There are two big fat wires and two thinner ones. On the old starter, each one went to a separate terminal, and I replicated that order on the new one.

Thing is, a lot of the threads I'm reading say that the two fat wires need to go on the same terminal, so I'm a bit confused. Maybe my previous starter was wired differently...


Originally Posted By: JHZR2
So you have a solenoid and a line to the battery, right?

Yes.


Originally Posted By: JHZR2
What would a stuck solenoid do? stay energized burning electricity, while the starter would disengage when spinning fast enough, right?

I would think so.
 
Originally Posted By: eljefino
You might want to leave your battery unhooked. In case of fire, if something like the solenoid is guzzling power.

Done.
 
Originally Posted By: Chris142
Could the big B+ wire be grounded somewhere like right at the starter?

Nope.
 
Ready for an embarrassing admission?

I may have connected the battery to ground through the solenoid. Hopefully I'll get a chance to get back at it tonight...
 
...and I just realized that that was exactly the kind of mistake that Chris142 was proposing and that I rejected out-of-hand. I suspect I'll be eating my foot soon.

On that note, thanks, everyone for your help so far.
cheers3.gif
 
Boy, do feet taste bitter.

Both fat wires are now on the same terminal, and all is well. Before, either the battery + wire or the alternator + wire was connected to the ground post on the solenoid. I'm amazed the symptoms were as mild as they were, and that nothing is obviously fried -- yet. I really, really hope I've heard the last of this stuff for a long time.
 
Originally Posted By: HTSS_TR
You're lucky.

Quite. I have no idea why my car still runs.

It's a slight bit rough at idle, but that may be because the fuel trims have been reset. Let's see what happens in the next few days.
 
you had the alternator (+) going to ground. The whine was it working at full tilt until it shut down.
 
Originally Posted By: meep
you had the alternator (+) going to ground. The whine was it working at full tilt until it shut down.

That makes me feel better about replacing it.
 
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