Car Died On The Road... Is It The Alternator?

[eluminator]

I would suspect the battery cable connections. I would remove them from the battery and clean them up and re-attach them snugly. If your cables attach to the posts on top of the battery, you can get a special wire brush to clean the posts and the cable connections. You should see shiny lead on the surface when they are clean.

And don't forget the other end of the cables. The ground (black) one is simple. It probably bolts to the engine.

The connection of the wires to the battery can fool you. They can seem good to the casual observer when they aren't good. When you start the engine 100 or more amps goes through these connections. This will do strange things to the surfaces of the lead unless the resistance is very low.

 

[Lurker]

One final thing to consider. I think you said this is a 1990 vehicle. That makes it about 15 years old and based on its age, it may have well over 200,000 miles on it by now. Even if the mileage is considerably lower than that, it's age is still a problem. In any case, this car is most likely on its last legs and you might want to think about replacing it at some point. Do you want to spend money on repairs at this point or is it time to give up and apply that money to a newer car? The cost of an alternator replacement could be in excess of the market value of the vehicle.

 

[Wingerr]

My bet is on an intermittent battery cable connection- I'd go with the load test Minjin outlined, checking voltage at the terminals as well as the battery posts. Don't bother removing it for an offline test. 13.5 volts while running indicates the alternator is fine. Intermittent problems are hard to pinpoint sometimes, so you'll have to try to induce the failure with jiggling or extended running to heat things up.
The no-start being characterized by symptoms of no cranking action indicates a simple power loss, not anything to do with ignition modules, fuel systems, etc.
If you lose the battery connection while driving, it can very well stall out even if the alternator is okay, if you introduce a sudden load like applying the brakes. It may result in the voltage dipping below the requirements for the ignition and injectors, and stall out before the alternator can compensate. Not advisable to disconnect while running, for the reasons stated before.
Check the cable connections on the other end (not just the battery end), because they're often neglected until problems crop up. Remove them, wire brush them, and generally clean them up before reinstalling.
A 1990 car is still new in my view- /ubbthreads/images/graemlins/smile.gif My 1993 Saab is my "new" car right now!

 

[markdi]

most cars when the alt is good and the engine is running have around 14.5 volts at the battery.

my 88 grand am never causes me any electrical or computer problems.

but I have cleaned the main ground to the engine.
and the electrical connectors have silicon boot/seals

oh and get this

the battery connectors on my old car are side post and they have seals on them(factory stock- original-never replaced)

no part of the connection between the connector on the car to the terminal on the battery is exposed.

my battery terminals/connectors(on the car or battery) have never needed to be cleaned - ever

I have owned it since 92.

why all cars are not this way is a mystery to me.

they did a lot of things right on my old car.

every thing on it works and works well.

 

[Wingerr]

But unless he's going to trade up to an 88 Grand Am, he has to find out what's going on with his car-
How long do you go between battery replacements when running at a constant 14.5V, assuming it's not still on the original battery? If you measure it when it's cold, right after startup, the voltage is higher, but afterwards, I would consider 14.5 to be a bit on the high side. So long as you have no problems, I guess.

 

[markdi]

my mom's 97 mini van and my old ford curier truck
both charge at more than 14 volts

my other grand am with the std quad four charges at the same voltage as the one with the w41 ho quad four.

batterys last me between 5 to 7 years.

I think this is the second battery I have bought for my 88.

I had a mazda that would blow the diodes in its alternator one at a time. dc voltage would go down and ac noise would go up-- I could hear it in the radio.

 

[Saaby]

[ QUOTE ]
A 1990 car is still new in my view- My 1993 Saab is my "new" car right now!

[/ QUOTE ] /ubbthreads/images/graemlins/grinser2.gif

Anyway, here's an excellent article to read before you decide it's time to buy a new car. Even if you don't agree with the article there's some good, solid advice in there.

 

[markdi]

I would love to have a newer car.

I am not in love with grand am's or quad four's.

I just keep fixing it every time it blows a head gasket

about every 80 to 90,000 miles or so.
I take the whole engine out of the car and replace every
gasket on the engine and clean and inspect every thing.

74,000 miles or so to go till this head gasket pops.

I bet the head gasket would last longer if I drove slower and did not punch it all the time.

and I bet my car is one of the uglyest owned by a cpf
member.

needs a paint job bad.

a good honda car would probably last me the rest of my life.

 

[SilverFox]

Hello Lurker,

My wife and I were amused by your comments...

Ryan, thanks for posting a link to that article. It makes sense to our family.

We just dumped about $1000.00 into our older Volvo. Older Volvo's do not have much meat on the disk brake rotors, and every 10-12 years you have to replace them.

Overall, we have spent close to $12000.00 on repairs on this car. It is probably time for a new one. The body is crap, but it runs very well.

Oh, did I mention that I bought it brand new in March of 1971? It has 330000 miles on it. Next month it will be 35 years old.

My other vehicle is a 1953 GMC... and my son drives a 1963 Caddilac...

Love the classics.

Tom

 

[Draco_Americanus]

[ QUOTE ]
Lurker said:
One final thing to consider. I think you said this is a 1990 vehicle. That makes it about 15 years old and based on its age, it may have well over 200,000 miles on it by now. Even if the mileage is considerably lower than that, it's age is still a problem. In any case, this car is most likely on its last legs and you might want to think about replacing it at some point. Do you want to spend money on repairs at this point or is it time to give up and apply that money to a newer car? The cost of an alternator replacement could be in excess of the market value of the vehicle.

[/ QUOTE ]

I persoanly do not use the market value of a vehical based on what I will spend on repairs, for Me it's the overall history the vehical has had while I owned it and the condition of the vehicle. I also assume by the time I am done with a vehical it's scrap! You should see My s-10, most would have scraped it 10 years ago, but if 100 bucks will keep it running another few months, thats better then a car payment!
Anyway by reading the posts I too sugjest checking the ground cable.

 

[Draco_Americanus]

[ QUOTE ]
Minjin said:
For most people a car is the most complex machine they will ever own, yet they have no desire to learn anything about or observe the behavior of their own car.

It always amazed me when I worked as a mechanic how oblivious people are to problems. No, the car shouldn't be shuddering when you're accelerating from a stop. No, you shouldn't hear loud bangs every time you hit a bump or small pothole. No, you shouldn't have to turn the steering wheel half a turn before the car moves in that direction...

Mark

[/ QUOTE ]

This is too true, but I will also say that there are certian things one may not realy notice, I try to be as absrvent as posible but I failed to notice the gross play in my Jeep's steering wheel untill after I drove another vehical, I promptly got that fixed.
As for an alternator failing under load, I had that happen with my one older buick, the lights dimmed, the radio made a "putt putt sound" I then learned to not get cheap replacemnt parts, I built a voltage monitor and pluged it into the cigerette and watched the voltage very up and down with just the turn signal on.

 

[Samoan]

get your relays switches and sensors checked as well. There are plenty of relays and sensors that are designed to kill your engine if they pick up a bad signal.

I was haivng very similar issues with my ZJ a couple months ago and a new ESO relay fixed everything.

-F

-F