Ok so I'm a new third gen owner; and am patiently working on one issue at a time. Granted this vehicle isn't being a pita....Since I'm a dealership technician it's hard for me to adjust sometimes to the 22 year gap in technology lol...

So I've got an 89 camaro rs with the 5.0 tbi engine

I noticed an erratic charging system voltage, more so when hot it seems, and with that comes a rough running 305. Now, the alternator is new, installed it myself. It's like the alternator can't put out enough amperage to run everything on the vehicle and once the voltage drops so low it effects the ignition, hence the rough running. The problem I'm having is I can not figure out why the voltage doesn't stay in the 13-14 volt range. Keep in mind this is with the a/c off, lights off.....SOMETIMES it will remain in what I would consider the normal range. Any guidance would be appreciated considering this vehicle is two years the elder of myself lol

 

Have the alternator tested. "New" doesn't mean good, it only means new! I've bought plenty of "new" parts that were not good, alternators included. The last "new" alternator I bought was actually overcharging my system, making my lights flicker, guage read weird voltage, etc. Just about all parts places test alternators in the car for free.

And - get this notion into the heads of your fellow "technicians"! NEW DOES NOT MEAN GOOD!!!! That's why you guys now-a-days are called "techs" instead of "mechanics". In today's "disposable" society, repair folks are now trained to replace rather than repair. And it's been very wrongly implied by such practices that, new parts are always good parts, when in fact they are actually more prone to manufacturing inconsistency and failure than ever before. It's cheaper now (with worldwide overnight shipping available) for manufacturer's to make more and faster, and neglect QC measures in favor of "we'll just ship another one if it's bad".

How many alternator/starter repair shops do you know of? 30 years ago, every town had one. Today, hard to find one anywhere. It's just cheaper to make another than to repair, such as the case with everything in our new disposable society.

 

Honestly the more I think through it and study the schematic I'm suspecting high resistance through visible link G....I will perform a voltage drop test on the circuit later this evening when it acts up to verify.

I totally agree about the whole replace not repair. As a Hyundai technician I can tell you this....we don't rebuild, but ONLY REPLACE transmissions, electronic tilt/telescope steering columnscolumns, engines, and many other electronic components. The only thing we rebuild are power seats! When I questioned our district rep. she simply said its due to liability. It's more beneficial to hang new parts on cars than rebuild due to the risk of something going wrong!

 

Curious as to what you find. I am having a similar problem.....

 

Well I had the car act up today finally; armed with my DMM I went under the hood. Here are the results from my testing with the engine idling in drive with the e-brake pulled...

Tan Wire- 12 Volts
Small red wire- 12 volts
Large gauge red wire- 200 mv

Once again this problem comes and goes...very intermittent

EVEN with a faulty alternator the large gauge red wire should still read battery voltage even with no alternator output. I'm now going to inspect the B circuit for an open or high resistance. I'm now wondering if the previous owner shorted out the b circuit while doing work on it to the point where the fusible link is partially burnt. High resistance should appear while the circuit is operating and would be more noticeable once heat has built up. Maybe my new diagnostic step will be to run a temporary fused wire from the B terminal to the junction block nearest the battery??

I will update as I continue to chase this problem down!

 

Hello I did a search and after reading this thread, my 87 gta is doing the same thing. I'm on alternator # 4 which is failing when exposed to the high operating temp. any inputs?

 

 

This is my problem exactly, really wish you had solved it

 

Remanufactured Delco/Remy #10463015 or 321-313