1988 Chevy Celebrity Charging System Not Charging

Home  \  Repairs & Maintenance  \  1988 Chevy Celebrity Charging System Not Charging

Hopefully someone can help me out here...

I have a 1988 Chevy Celebrity. It's the 2.5L 4 banger Iron Duke motor. This one's distributorless. It's got AC.

The problem I have is that the car runs off the battery until the battery dies. The alternator doesn't charge the battery. I don't think it does anything.

To make a long story short, the alternator won't charge the battery. I've had a total of two "new" alternators and four new batteries.

I parked the car for three years because it was a third car, but now my second car has thrown a rod and I need to get this one going. With the fourth new battery, the car fired right up as if it never sat at all. It idled for several hours then I shut it off and couldn't get it to re-start.

The battery now reads 10.4VDC.

There is a schematic of the engine wiring here (http://www.autozone.com/servlet/UiBroker?ForwardPage=/az/cds/en_us/0900823 d/80/0f/40/0f/0900823d800f400f.jsp) . The diagram for my engine is called 0900823d800f4041.gif.

The diagram shows two red wires coming off the alternator. The large red one goes to the starter. The smaller red wire goes to a fusible link then on to a relay. I have continuity from the wire plug on the alternator all the way to the relay. I'm not sure what that relay is because the colors of the wires on it don't match any of the relays shown in the electrical systems diagram. But the fusible link is good.

On the positive terminal of the battery I can test the continuity of the wire up to the first fusible link. I haven't been able to trace where the wire from the fusible link goes. It's orange, not red like the diagram I posted says. I'm pretty sure that fusible link is good because once I start the car everything in it works- the radio, lights, horn, AC, etc.

I'm stuck now. I know the alternator and battery are good. The fusible link from the alternator is good. If I charge the battery on my trickle charger the car will fire right up and run smooth. What do I replace/test next?

posted by  DaveB

Checked the regulator? (don't know if it was in the alt. that year or not...) if not then it is indeed most likely your alternator.

posted by  88GrandPrixSE

wow u didnt read? he got like 2 alternators.. hell just buy a new one to make parts guy happy..

2 alternators and 4 batteries? it would have cost less to take it to a dealer ship and found out the problem in the first try.

well since u spent all that money DYI then we might as well help u.

anyways u should have 4 wires to the alternator. get out ur handy dandy voltmeter or test light. with key on, engine off, check each wire for batt voltage. im sure one of em dont have it..

post back here with results..

posted by  thongsai

I'll check them all this morning. Hopefully it warms up. It's 28 degrees right now. :doh:

When the car was running earlier this week I metered from the large red wire going to the starter. I put the common lead to chassis ground. The meter would read around 12.8VAC and quickly drop to zero and stay there. It dropped so fast it's hard to see the numbers, so it may have started above 12.8V, I'm not sure.

I still have the first alternator that I bought. I got lazy and never returned the core, so it's like new still wrapped in the original box. I can swap it in today as well and take some readings from that one to compare the two.

I checked the continuity between the positive battery lead and ground looking for a short but it was wide open.

The regulator is internal to the alternator on this car.

Thanks in advance for the help. I really need to get this thing running.

posted by  DaveB

Two more things I just thought of.

I was trying to recharge the battery this week by hooking jumper cables to a friend's truck. We let it go for an hour with my engine off and key out and his truck running and the battery wouldn't charge at all. His jumper cables were reading 14 VDC but the battery stayed at 8. We removed the battery from the car and tried to charge it and it jumped from 8 to 12 V in about 15 minutes.

Also, I remember when I was driving this car every day three years ago that occassionally if I went through a very large puddle of water the engine would die and the car wouldn't start for the next 30 minutes or so. I never did find what was getting wet and stalling the engine, but it rarely happens so I didn't worry about it. I could drench the underside of the engine with a garden hose and it would keep running.

posted by  DaveB

Hate to tripple post, but I just got inside from freezing my @ss off reading the alternator again.

I got 9.8VDC across the battery cables. After it warms up a little more I'm going to start trickle charging it before people start posting that my battery is too low.

I disconnected all four wires from the alternator and checked them. All four read 9.8VDC from the wire to the positive terminal on the battery.

I had the key in the on position.

posted by  DaveB

sounds like your having a voltage drop, test your cables(car running) by holding your common lead to the (-)post on the battery and the positive lead to the alternator housing, this tests your (-) cable . then check the positive cable by holding your com. lead to the (+)post to your battery and the positive lead to the biggest cable on your alternator. your readings should be.3v to .5v. if they exceed this range clean the teminals(both ends) of the cable that failed and retest.

posted by  carlos

sounds like your having a voltage drop, test your cables(car running) by holding your common lead to the (-)post on the battery and the positive lead to the alternator housing, this tests your (-) cable .
When I do this I read 0VDC.

then check the positive cable by holding your com. lead to the (+)post to your battery and the positive lead to the biggest cable on your alternator. your readings should be.3v to .5v.

This also reads 0VDC.

If I reverse the battery terminals you mentioned (+ to alt housing, - to starter wire from alternator) both of them read the battery voltage, which happens to be 10.7VDC right now.

posted by  DaveB

eh??>? disconnect the 4 wires, make sure none touch metal. turn key on.
then get voltmeter, black lead to good engine ground.. and red lead to check each of those wires.. if all good then do the suggested voltage drop test. most likely its high resistance in the big red wire.. but do these tests b4 you start buying parts.

posted by  thongsai

So what if he's had 2 alternators? I've had 4. GM made really crappy alternators throughout that era.

posted by  88GrandPrixSE

Really bad paint too...

posted by  DaveB

i saw the post above about the voltage regulator i was having the same problem with my 1970 nova, also if you turn your car on with jumper cables and the battery charge is under 12.6 volts alot of the time it will kill an alternator or a voltage regulator, if you get a voltmeter and turn the car on the battery should read above 13volts and about 12.8 volts turned off. i would get it checked or take it to a mechanic im sure hell run that test for you for free.

posted by  rage141414

When I do this I get the battery voltage on all four wires, same as when I did the voltage drop test.

I'll completely remove the big red wire from the car and measure the resistance through it tomorrow. I'm going to put the other new alternator and battery that I have in it and try the tests with those as well.

posted by  DaveB

ok do a voltage drop test
do this with wire in a load.. car running.. the big red wire from battery to alternator labeled B+ or something like that.

anyways set meter to volts.. put red to alternator output and black to battery positive.. thats right positive. tell us reading..

checking wire resistance isnt enough.. the wire can be a huge wire except very thin in middle. this will pass resistance test but wire is BAD

like i said have car running. to put a load on the wire.. then voltage drop test is the only way to check wire. no need to remove anything.. have all wires connected during voltage drop test..

so in short. test 1: Battery Positive and Alternator output
test 2: Battery negative and alternator Case

both done with meter set on Volts NOT OHMS and while car running. post back

posted by  thongsai

My god yah, My 88 GP is shedding, (It's actually the primer that was bad btw :P) I gotta hand wash it or the pressure washer will blow off a load of paint, getting it painted once the snow melts though, so it's no biggy.

posted by  88GrandPrixSE

i didn't really read, but if you haven't already, just go to sears and have them hook it up and check it out. it'll cost you like $12 and save you lots of time and energy.

posted by  BMWGuru

didn't read any of the posts, but since it's an 88 celebrity and you are going to ruin too much by doing the following, here goes:

start the car up
pull off the battery terminals
if it stays running your alternator is fine and you have a bad battery.
If the car shuts off you have a bad charging system. Check the little in line fuses gm puts in everything, try running a new wire directly from the output side of the alternator to the positive on the battery and see if it starts charging again.

posted by  carls47807

hi there why do you try to your engine distributor, wirrings coming from the alternator going to your battery sometimes it happens that the electricity that alternator gave to your battery jump out due to grounded so try to check all the wires came from alternator.

posted by  marpsa

Your Message