1998 Regal Gs battery light and tranny whine after new tranny

[Drgsxr750]

I've got 98 Regal GS (3.8 supercharged and 4t65e HD) with 93xxx miles on it and I'm having a bevy of problems.

First Problem: The tranny went out so I went online and got another one with 30xxx miles on it. Less then 50 miles later the tranny whines when it's warm and I can smell it getting hot. Obviously, it could be just a random bad tranny but I doubt that it's the case because when I dropped the old tranny it had markings from another salvage yard and it was from a GTP. So this car has blown 3 trannys in less than 100K. So first question: could a car actually cause a tranny to go bad? Second question: what would you guys check and what should I do cuzI don't have the money for another tranny every 50 miles LOL.

Second Problem: After replacing the tranny the battery light would come on after 30 secs of the engine running. Alternator and battery both test good at autozone. I thought I might have pulled a ground somewhere when I was wrestling the tranny into place but I can't see any loose wires. With the engine off I get 12 volts and with the engine running I get the same so there is a problem somewhere in the charging system. As I said before, this problem started after replacing my tranny. What would you check?

Thanks for very much for your knowledge and input. I'm sorry for the long thread and if I've violated any online rules by combining two threads. I have poor online etiquitte I guess. Anyway, I've been trying to keep this darn thing road worthy but it's taking all my time!! I love the car but I'm starting to think it's cursed.

[BNaylor]

On the tranny whine it sounds like high line pressure probably caused by a bad pressure control solenoid. Get it scanned and see if a P1811 DTC is stored.

Did you check the main ground located at the transaxle/engine. Driver's side top of where the transaxle and engine mate up.

Also, how are the upshifts. Any hard or erratic shifting?

[Drgsxr750]

Bnaylor,
I haven't noticed anything like that but then again once I heard the whine I shut her down that very sec because I didn't want to cause any more damage. I noticed what seems like delayed shifting but nothing too serious. On that ground, when I was replacing my tranny I noticed someone used an impact to tighten the nut on so I ended up destroying the ground as I removed that bolt but I repaired it or so I thought. I just added a new ring terminal and called it good. U want me to slap a voltmeter on it and see if I get a full 12 volts on it? Thanks for your timely response. I really appreciate your knowledge.

[Drgsxr750]

I took her to a friends today (10 miles highway) and the car seemed absolutely normal until coming home. I made the final left hand turn and the battery light came on. I shut her down and tried to start her again and click click click dead battery. Tranny was smooth as butter and no whining. I don't know what to do lol because the light was off until the last turn and bam battery is dead. Help please lol

[BNaylor]

Are your sure the battery and alternator are good? Sometimes the Autozone test shows good but the battery and alternator could still have a problem. The battery could still have a bad cell. If you get it started what does the voltage read across the battery positive and negative terminals at idle using a multimeter or at the output of the alternator.

[Drgsxr750]

The Alt is bad. At the battery I have 12 volts and at the output of the alt I have 0 so that pretty much solves it. Thanks for your help. I first suspected the alt but when autozone told me it was good I was floored. I've never felt an alt spin so freely. I guess that tester is a piece of crap. Thanks for your help Bnaylor. Additionally, I'm gonna start driving my car a little further each day to see if I can reproduce the whine and I'll advise you what I notice. Thanks again for your help.

[Drgsxr750]

Just replaced the alt and it didn't help. I have no idea what could possibly be going on. Any suggestions?

[BNaylor]

Have you checked all the wiring from the alternator to the battery? If you can get it started what voltage are you reading across the battery positive and negative terminals at idle?

[Drgsxr750]

Sorry for the tardy response but I had a major test that I had to study for now thats past I can devote more time. Soooo, the battery at idle is at 12 volts or less. the alternator output to negative battery is 0. As I said before I replaced the alternator and it is doing the same thing. I'm starting to think that the alternator turn on is not working properly and according to my hayes manual that little 4 prong plug runs to the PCM. I don't have any more money for a PCM so if that's the case this car is as good as junked lol. What should I test for next BNaylor? Thanks for your help.

[BNaylor]

When I get a chance I'll check the GM Regal Factory Service Manual. The PCM does monitor alternator output to trigger the battery/charging system light and monitors voltage if too low like around around 10 volts. Very seldom will a PCM cause the alternator to have a zero volt output or not charge the battery but possible I guess.

[Drgsxr750]

Do you think hard wiring a switch to the low voltage would be a good idea? I really don't want to do that but I don't want to replace my PCM either. Please let me know what you find. Thank you so much for your help, bnaylor!

[stripe]

Originally Posted by Drgsxr750

Sorry for the tardy response but I had a major test that I had to study for now thats past I can devote more time. Soooo, the battery at idle is at 12 volts or less. the alternator output to negative battery is 0. As I said before I replaced the alternator and it is doing the same thing. I'm starting to think that the alternator turn on is not working properly and according to my hayes manual that little 4 prong plug runs to the PCM. I don't have any more money for a PCM so if that's the case this car is as good as junked lol. What should I test for next BNaylor? Thanks for your help.

I had a Regal that did close to the same thing.

But the lights (ses,etc) flashed a lot.

Long story short the battery was no good.

I got a used battery and thought it is good.
Turned out the used battery wasn't putting out over 600 amps.
(only about 575 amps.)
So it did not start next day.
I took the battery back and had it rechecked.
These cars need over 600 amps at crank to work right.

You may want to check your battery.

Cheers
Stripe

[richtazz]

Inspect the large wire that runs from the alternator to the battery (the one that hooks to the threaded stud on the alt). This wire should have battery voltage at all times (or higher when the vehicle is running and charging) as it is a direct connection between the two. 0 voltage at that point would indicate a broken wire between the alternator and battery.

[BNaylor]

The best thing to do is remove the output connection from the alternator ( red wire/cable) and to the battery and starter. Ohm the cable out point to point and check for any shorts to ground. Also, keep in mind those cables have fusible links that could open up.

From looking at the circuit also check the ALT SENSE fuse (10 amp) at the main engine compartment fuse box. At the alternator 4 pin connector this should be an orange wire so if the fuse is good check for voltage input. Only two of the four pins are used on the 4 pin connector. Pins D and B. Pin D is alternator sense and Pin B is the monitor output (Generator Terminal L Output) to the PCM module which should be a red wire. Pins A and C are not used.

The voltage parameters that the PCM monitors for is 11.2 v (low) to 16.5 v (hgh). If the voltage is too low or high the internal voltage regulator in the alternator causes a shunt condition at the field rotor windings of the alternator meaning no output.

[Drgsxr750]

Bnaylor, I did what you suggested and found a break in two wires comming from the main harness. Both of them had greenish corrosion so the breaks looked pretty old and I must have pulled them out when I was wrestling the tranny. Anyway they are both Red and one is much thicker then the other I can't see where they go but I'm assuming they go to the battery in some fashion. I'll take pics if you want and maybe you can tell me where they go so I can extend them lol