Alternator problem!!! HELP!!!!

[bennelson]

Hey everyone,

My wife's car just started having a problem.

She said it died at a stop sign when she had to run out at lunch today.

I took a look at it when I got home.

After starting it, the idle speed was only a little over 600 RPM. When I turned on the headlights and fan, I could see the dome light dim.

The scan gauge said that engine load was at 25 while just sitting there idling. It jumped up to 32 when I turned all the other electric things on.

There seems to be a rattling noise coming from the alternator. Is the bearing on the alternator going bad? That would increase resistance to the engine if the alternator doesn't spin well, right?

What happens if we keep driving the car and that bearing gives out? Would that lock up the serpentine belt, loose the power steering, and kill the engine?

I don't think an alternator is that hard to replace, but I wouldn't be able to do it until later this weekend.

Is this something I need to take care of immediately!?!?

All advice welcome!!!!

[RH77]

Yikes...

I recommend taking it to one of those big-box auto parts stores like Auto Zone or Advance Auto: they'll test the charging system free of charge.

It could be the battery and/or the alternator.

The sound may be the added stress on the alternator to keep the charge up on a dead system. If it seizes, it would likely throw the belt or you'd hear the screeching of it slipping.

Not something I would wait to repair, IMHO...

RH77

[Ryland]

grab the pully and wiggle it, you should be able to feel the bearing play, if it's still charging but loud then you are correct in the bearing, a rebuilt alternator is going to be the cheapest rout to take.
two things to check would be the belt tension, and the age and voltage of the battery, but what is most likely happening is the brushes aren't making solid contact because of bad bearings.

[Coyote X]

easiest way to test if an alternator is charging is to start the car then unhook the battery ground wire. If the car dies instantly then the alt is dead. The rattling could be the brushes came apart and are just rattling around inside the case.

After that idle the car about 5 min and then feel the alternator and if it is really hot the bearings are also shot. If they seize up it will at best just shred the belt and leave you with no belt driven accessories. If the alternator isn't really much different temperature than the rest of the stuff under the hood then it will probably be safe to drive it. You just have to keep the battery charged somehow.

If you do drive it keep track of the temperature of the alternator, if it starts getting really hot then the bearings are getting ready to seize.

[bennelson]

I went to the local big box auto store this morning and had them do a battery and alternator test.

Both checked out ok. I don't think the particular guy who was helping me was real bright - he could follow the directions on the machine, but wasn't very helpful on offering any advice.

No that I have driven it, I can say it feels like there is a lot of drag on the system. Like the parking brake is left on almost.

It idles at 600-650 rpm, and something in the engine compartment has a little bit of a rattle, and it sure sounds like the alternator

If I let off the gas while driving, the RPM drops real fast, and the cars slows, rather than that coasting effect you usually get when you let off the gas in an automatic transmission car.

I have never worked on a serpentine belt or an alternator before. I don't have a manual for this car, it was always worked on by the shop before.

I think I need to buy a manual, and read the sections on the belt and alternator. Then on Saturday, take a look at both, and buy and install whatever is needed.

The other weird thing about this is that the Scan Gauge was reading right around 50 mpg @ 2000 rpm while I was driving anywhere between 30 and 45 MPH. I would think the car should be getting really bad economy right now. What's with that??!!?!

[metroschultz]

It sounds as if your alternator is dying. A slow and painful death.

No disrespect Coyote, but, Do Not disconnect the battery to check your alternator output.
Bad JooJoo
Any car made after 1989 with on-board diagnostics can (not always, but why risk it) Burn the computer internals when you disconnect the battery while the engine is running.
Both of the cars you have listed that are ICE have weak (not electrically tolerant ) computers.

I would spring for a new (re-manufactured) Alternator.

Pull the battery and put it on charge while you replace the alt.
It is not a difficult task on either of your cars. ( I don't remember if you told us which car)
If you don't have a load tester then carry your battery to the corner gas station and ask him to test it for you, after it has charged.
I do not put much faith in the Big Box Auto Stores. They are usually nice people, but they don't have real world experience. IMHO
Anybody can read an instruction pamphlet, but not everybody knows what they are looking at when it comes to resultant data.
The local shop should Help you and they can also intelligently install your battery or cover the warranty if need be.
If you have a shop you have been dealing with over the years, let them help you. Tell them you need to do the repairs yourself for monetary reasons and offer to give them some sort of compensation,(not necessarily money) ("I'll bring you some of my wifes killer brownies next batch")
for their efforts.

BTW (Open offer to ALL Ecomodders) if you find a car within 100 miles of 23452 let me know and i can go look at it for you.(may have to wait til Sat) Most vehicles in this area have very little rust on them. If it is cheap enough i will go ahead and pick it up. You will have to get it from here though.

Let us know how this turns out.
S.

[RH77]

First, is this on the Sunfire, BTW?

Originally Posted by bennelson

I went to the local big box auto store this morning and had them do a battery and alternator test.

Both checked out ok. I don't think the particular guy who was helping me was real bright - he could follow the directions on the machine, but wasn't very helpful on offering any advice.

Bummer. It's hit or miss, but sometimes the free load test can help. Let's assume that the results are correct for a moment...

Originally Posted by bennelson

No that I have driven it, I can say it feels like there is a lot of drag on the system. Like the parking brake is left on almost.

It idles at 600-650 rpm, and something in the engine compartment has a little bit of a rattle, and it sure sounds like the alternator

If I let off the gas while driving, the RPM drops real fast, and the cars slows, rather than that coasting effect you usually get when you let off the gas in an automatic transmission car.

What does the SG read on VLT? Also, if you have a voltmeter, test the voltage of battery, at the battery (engine off).

Also, pop the car into Neutral and coast at say, 35 or so (maybe even a parking lot). Take note of any accessories: power steering action, turn on the A/C and see what happens.

Why I ask, the possibility of different part failure could exist (water pump, A/C clutch bearing, transmission -- just guessing aside from possibly the obvious).

Originally Posted by bennelson

The other weird thing about this is that the Scan Gauge was reading right around 50 mpg @ 2000 rpm while I was driving anywhere between 30 and 45 MPH. I would think the car should be getting really bad economy right now. What's with that??!!?!

Check the settings of the SG for proper displacement -- could've gotten bumped down to a smaller engine size or other settings. Otherwise, wierd.

I wonder if resetting the ECU could provide some answers -- maybe the computer is freaking about something...

I agree with the Schultz on this one -- may have to take it to a local mechanic if you can't pinpoint the problem...

RH77

[Whoops]

My first guess is the alternator. If you have a Voltmeter, it should read around 12, when the car is not running and it should pick up to 13.5 volts+ when the car is running.

On the serpentine, on my 98 Chrysler it has a tensioner pulley. You have to use a long 15mm box wrench to release the tension. Their should be a belt route diagram, under the hood. If their isn't, then draw yourself one, before you remove the belt. Once you have the belt off, their are two bolts, mounting the alternator to the brackets. Their are a couple of nut's to remove, attaching the wires to the alternator. Be sure to remove the positive battery cable, before you start, sou can't short out anything.

[bennelson]

I ended up putting a new alternator on. After lots of dinking with it, the problem wasn't actually with the alternator, but the old was was getting noisy, and it was at about the right mileage for a new alternator, so I just did it.

Seems that the power problem was because of low automatic transmission fluid!! 2 and a half quarts low!! This car doesn't have a tranny fluid dip stick.

You have to raise the car, pull out a dran plug and stick your finger in there to check it!!!!!

Car is much happier now.

[RH77]

Originally Posted by bennelson

Seems that the power problem was because of low automatic transmission fluid!! 2 and a half quarts low!! This car doesn't have a tranny fluid dip stick.

Welp, that was my last guess...

But, good thing you found the problem!

RH77