NO AMMETER!

I am in fairly desperate need of some advice.

A week ago I completed the 130 amp 3G Alternator upgrade. I had wanted to do this for a while—a new job has me driving home an hour after dark, and with the headlamps on (although the lighting system is 99% LEDs), the EATC on 72 degrees (it’s ONLY around 105 by then [!!]) and the various other systems at work, I was concerned that the stock one was eventually going to fail (I’ve had this one since around 2004). (Backstory: when I first got the car I was going through a battery a year—just the usual parts store crap—and an alternator every two or three; oh, and an ignition switch about the same. Well, Jeff’s Headlamp Relay upgrade solved most of those issues, as well as a good battery [like a DieHard]—but again, I haven’t driven the car regularly at night in at least 20 years).

I got it from Pa Performance—enough others on here had done the same so I wasn’t in the mood to price shop, just get what’s recommended. I was chatting online with Customer Service and also ordered the Premium Long Wire, which after it arrived I could see it was way TOO long—got the Short one instead. They had kind of freaked me out when I was told the 130 would burn right through a 10 gauge wire—DOH!—even though I tried to explain that I was upgrading TWO OTHER 10 gauge wires as well, which should cover the extra amperage. So not wishing to take a chance I used that wire (Cable?!) with its 200amp fuse for the Starter Relay to Alternator Output connection.

I followed Jeff’s Tech Article pretty much to the letter—except for that heavier gauge PaPerformance connection. When I was all done—and with fire extinguisher handy (I told you they had kind of freaked me out!), I reconnected the battery and started it up. All good—nothing was overly hot or even warm (although everything is warm when it’s still 95 at 5 am!), voltage started out at around 14.45, eventually came down to 14.20. Everything was powered on to draw up the load. Great job! I’d have a beer if it wasn’t almost dawn.

ONLY—there is no ammeter. Nothing. Right on the line, no charge or discharge, which usually shows a slight charge.This morning I stuck probes in the Red/Orange wire—one of two spliced (#S261) by the green wire with the 14 gauge fusible link, at one end of the yellow shunt wire; and the Yellow/Light Green one (by the other end of the yellow shunt wire, splice #S262). According to the EVTM, these are the wires that connect to the ammeter. There is continuity, so nothing is fried there. I started the car and measured the voltage it was getting—with the MM set at 20 and the lights on: 0.02. Lights off: 0.01. Now, I have never tested the ammeter this way before, so I don’t know what that number is supposed to be—but that obviously seems very low to me.

Here is what I have: red 10 gauge wire spliced into the start of the 37 Yellow shunt wire (splice #261) to Alternator Output screw; red 10 gauge wire running from the ORIGINAL Alternator output wire (38 Black/Orange, which is at the OTHER end, splice #262) to the Alternator Output screw; 4 gauge red PaPerformance cable (with fuse) running from Alternator Output screw to Battery side of the Starter Relay (on the driver’s fender).

There are total of 6 wires that attach to that connection; amongst them the Viper alarm, etc.

I also replaced the Regulator plug, as mine was a bit corroded and nasty. There are three wires that form that connector: White, Yellow, and Green. The white Stator wire from the included Upgrade kit attaches to the White wire, in the center; the Yellow/White wire from the original plug attaches to the Yellow wire; and lastly the Light Green/Red wire from the original plug attaches to the Green one.

That’s it. I can’t understand why it doesn’t work! This is particularly disturbing in that, with the heat settling in and the Monsoons about to start—with nasty humidity—I have to start this troubleshooting work at around dawn and then quit after only an hour or two (once the temps start to rise), and put it aside until the next morning.

I know that the scientific and philosophical rule known as Occam’s Razor states that the simplest solution is often the most obvious. I’ve tried replacing the heavy 4 gauge cable with the one Jeff suggests we make (with a 175 amp fuse)—it didn’t help, and now the Red wire spliced with the Black/Orange former Output wire seems to get a bit warmer. So I put it back.

In various posts/clarifications Jeff has suggested splicing one Output wire (#1) to one end of the yellow Shunt wire, and the other (#2) to the OTHER end. I am tempted to try this, but that should not matter, as the Black/Orange wire that is spliced to #2 has continuity as is PART OF THE SAME SPLICE  (#262) as the yellow Shunt wire. How could that make a difference?

What are your thoughts? Is there something obviously (or not so) wrong with what I’m doing? Here is a diagram I drew up (it’s okay to download it, apparently the only way I can post it):

https://www.dl.dropboxusercontent.com/sc...gabuc&dl=0

I had carefully planned any Upgrade or Modification work for way before the heat started, but this idea seemed like a good one so I went ahead with it. And yes, I could go with an Aftermarket gauge, as I know the stock one is often incorrect. But I can’t get over the feeling that this doesn’t work and it’s part of a larger problem that will soon show itself, and hopefully not with flames and smoke. 

Any suggestions would probably be most helpful. Thanks in advance.

The Amp gauge is basically worthless, when I did the PA 130 amp I just did the amp gauge bypass. Recently I tried using a USB lighter adapter with a voltage readout. I rewired the lighter socket to be switched with the ignition so I could leave it plugged in. What I found is that didn't really give me battery voltage, it was reading mostly 12.5 - 12.8v. When I connected the USB adapter at the battery, I was getting the same 13.5 - 14.xx volts as the multimeter voltmeter would read at the battery.

Eventually I will run a relay using the switched lead that currently goes to the lighter socket for a trigger and battery power to the lighter socket for the USB voltmeter. For now (and the past 10+ years) I have been without any voltage monitoring but in reality, It's not that hard to determine when things aren't quite up to snuff. Maybe a year or so ago I noticed what seemed to be lower than normal voltage. Checked the alternator output and found it wasn't much over 12.5v, would read a little over 13v when started, but drop after 20 seconds, revving didn't change the output. Called PA performance, they had me send in the alternator, found an issue with the regulator, repaired it and send back all at no cost.

I would just rewire and omit the alternator circuit, I just used their short fused cable and everything has been working great.

I would just rewire and omit the alternator circuit, I just used their short fused cable and everything has been working great.

I think you mean, you would rewire and omit the AMMETER circuit, not alternator. 

Yeah, I understand that the stock ammeter is, to be kind, not the best—and thanks for your reply and suggestion. I do appreciate it.

But you don’t know the kind of person I am. It bugs the Hell out of me when something doesn’t work as it should. I want to know WHY (even if due to obsolete parts or feasible cost I can’t fix it). Especially in this case, when it worked okay BEFORE the upgrade, and by all accounts it should work okay NOW.

And, the corollary to that is—as I said before—how do I know that its lack of operation is not due to another issue that has yet to reveal itself? If it doesn’t work, then there must be a good reason, right? Without knowing that reason we cannot know that everything else is okay.

My first car was a 1950 Oldsmobile 88, of course full of gauges. I was taught then by experienced owners of other vintage cars to watch those gauges carefully—in those days they (mostly) actually worked as they should and it was sometimes all you had to prevent or fix a problem. And, even though the TC gauge is not very good, it has saved me from some trouble over the years.

It just eats at me to look at the instrument panel and see a non-functional amp gauge there.

As I said, I can purchase an aftermarket amp/volt gauge…but then my thinking is, “well the other ones are inaccurate as well, why not replace them too?”, and now I am on a whole different road. Plus, I have to figure out where to put it—or them, for that matter. The door pillar gauge setup has been long obsolete for our cars.

Vegas, as a nearby neighbor here in the Southwest you know how difficult it is to get anything done here during the summer heat (today it was 119–even in the garage it’s almost 105). I am not a complainer—I choose to live here and accept the consequences, have done so for almost 35 years. But in the same way that you guys in the East don’t work on your cars in the very cold winter months, we try and avoid that here.

So I must ask, again: does anyone (else) have any ideas?

Yes it is pretty hot, luckily I have a medium size evaporative cooler for the garage and the humidity has been very low so that is working pretty well, but still a little warm unless it's blowing on you. I've been procrastinating quite well on getting my G8 GXP back together. I had a good excuse before since the machine shop took over 6 months to finish rebuilding the LS3 but it's been back almost a month and all I got done since was stuff I could have done while waiting on the motor!

I did actually get quite a few things done to the tbird... it loves the heat! No rattles! AC is good (r12), runs cool, with the solid state IVR the gauges are pretty accurate except the AMPS and the floating ground adapter fixed up the Alpine stereo running through the factory EQ and amp (aftermarket speakers) and it sounds pretty good so no problems handling the 115* heat in relative comfort (so far...)

Yes it is pretty hot, luckily I have a medium size evaporative cooler for the garage and the humidity has been very low so that is working pretty well, but still a little warm unless it's blowing on you.  I've been procrastinating quite well on getting my G8 GXP back together.  I had a good excuse before since the machine shop took over 6 months to finish rebuilding the LS3 but it's been back almost a month and all I got done since was stuff I could have done while waiting on the motor!

I did actually get quite a few things done to the tbird... it loves the heat!  No rattles!  AC is good (r12), runs cool, with the solid state IVR the gauges are pretty accurate except the AMPS and the floating ground adapter fixed up the Alpine stereo running through the factory EQ and amp (aftermarket speakers) and it sounds pretty good so no problems handling the 115* heat in relative comfort (so far...)

Yeah mine has no problem with the heat either, other than the battery/alternator issues I used to have.

You’re still running R-12? I won’t ask the obvious questions as that could get both of us in trouble   . I switched to r-134a in 2015 and it is still running strong. Because I went through a period about 20 years ago when I was having A/C issues I have two rebuilt HR-980s lubed and vacuumed out, sitting on the shelf. The PAG oil doesn’t like oxygen—it will darken and thicken, I am told; if you’re going to store them you really have to put oil in them and periodically rotate the mechanisms so they don’t lock up. I designed a way to vacuum them out and then seal them tightly.

Is the G8 GXP the one you won in an auction? That front end really looks like a BMW, surprised they didn’t sue. 

When the heat dissipates in October I’m starting on the DIY IVR project. I ordered all the same parts as you, will likely be following your lead on that. I could be working on it now but it most probably won’t go into the car until then. And there’s also the engine rebuild project that has been ongoing for 2 years, without much progress (just no time). I hope to get more into that during this heat, in my home office/work area.

Yes on the R12... Passed the exam and received EPA certificate several years ago after reading through the online materials. Been buying R12 here and there off eBay but never have been asked for a certificate?? Use to have a Mark Vii that also used R12 too. Have two hr980's on the shelf too, actually also have the socket that fits the clutch retainer nut as the compressor on the car came without the clutch.

You know the drill about having a non-AC car in the desert! I learned that back in the late 70's when I moved to Tucson with a triumph GT6... talk about hot! When I would finally get out after a drive, it was much cooler outside! Still was a fun car though!

Yes the G8 is from the auction, was running fine, changed the oil w Mobil-1 (uses almost 9 quarts) then about a month later was chirping... cam and lifters had some minor damage (surprising how much noise some chips make). PO always used red line or royal purple 10-30w, I used Mobil-1 5-30w... coincidence??? Motor is refreshed, new cam (cam motion ls3 stage 3 high lift), new cam bearings, hv oil pump, rings, new johnson lifters, new pushrods (have to set lifter preload by length), timing set, balanced, heads refreshed (already had dual springs and titanium retainers... pre lubed and smoke tested, just waiting on me! Also have a new clutch (monster twin), sent the trans to tick performance for a refresh and added a MGW shifter. Should be pretty good once I get it all back together!

When you do the IVR, I gutted an old IVR to solder the wires leading to the adjustable regulator and left them longer so the regulator actually rests on the inside lower dash ledge by the headlight switch. I found that convenient when I needed to adjust it as it was reading a little low. Just needed to remove the lower center trim under the steering wheel and the regulator could be retrieved and adjusted easily. I'm close to 6.2v now and have hot oil pressure and temps around 1/3 at idle while pressure rises to 1/2 - 2/3+ at 2500 rpm. When cold oil pressure is ~ 4/5.

I'll probably start working in garage at night, that is after today as it's suppose to be the hottest day of this little heat spell (118* forecast).

When you do the IVR, I gutted an old IVR to solder the wires leading to the adjustable regulator and left them longer so the regulator actually rests on the inside lower dash ledge by the headlight switch.  I found that convenient when I needed to adjust it as it was reading a little low.  Just needed to remove the lower center trim under the steering wheel and the regulator could be retrieved and adjusted easily.  I'm close to 6.2v now and have hot oil pressure and temps around 1/3 at idle while pressure rises to 1/2 - 2/3+ at 2500 rpm.  When cold oil pressure is ~ 4/5.

I owned Oldsmobiles for years—my 1970 Toronado was my favorite car, and even as much as I love my TC, it still shares that honor. 4 barrel 455, Turbo Hydro-Matic 425, that funky rotating speedometer–what a car and a real pleasure to drive! Hemmings 1970 Toronado Buyer’s Guide.

General Motors often used both Pontiac and Oldsmobile to produce “Experimental” models. The G8 doesn’t sound like something an American car company would have even produced. *sigh*

I printed out the last bit of your post on the IVR. I like how you have it set up so you can easily access it, I was wondering about that. Thanks for all that info.

Well, I went back. I re-installed my previous alternator. Now, before anyone rushes into judgement, please understand that I did have good reason for doing so.

Let me start off by saying that I really wanted it to work. I’ve wanted to have a more powerful alternator for at least 31 years, ever since I had all those charging issues when I first got the car, as I’ve mentioned before. And I haven’t given up just yet—but more on that in a bit.

And, for the most part, it DID. Certainly there was more output measured with the multimeter than before—but honestly not all that much. I mean, I hadn’t had dimming headlights or any of that other stuff with my previous one, and for that I attribute Jeff’s Fog Lamp Relay fix and the replacement of nearly every incandescent lamp with LEDs.

It came down to really two reasons: first, there was the stupefying puzzlement of the Amp Gauge. Having already connected to one end of the yellow Shunt wire, I connected the second of the two 12 gauge Output wires to the other end of it and disconnected the former output Black/Orange wire that I had initially connected to—which as I said before was in near-desperation, as that wire is part of a nearby splice and was already receiving that current. I tried removing the heavy size 4 gauge short fused cable I had purchased from Pa Performance and replacing it with a 12 gauge wire (as instructed), believing that somehow it was robbing the Amp Gauge from current with its massive capacity.

(Yes, I know in BOTH cases that’s not how electricity works. While I don’t have any sort of electrical degree, I have been working with it for close to 50 years. As I said, I was getting desperate.)

I was already looking on Amazon at voltmeters and pillar mounts, figuring that was the way I would go, and probably add a temp gauge and perhaps oil pressure as well. So, no that wasn’t the main reason.

I was dismayed to see that the new alternator was pulling the engine down—causing it to bog down—stalling, rough idle, and so on. I would have to start the car with the A/C off, and still it struggled. If I dared to start with the A/C on, the cooling fan would cut in and out and eventually it would stall—then have difficulty re-starting. When I would get it going again I would have to raise the idle to about 1500 for several minutes before the idle settled down…and even then it ran rough and was prone to stall as soon as I let it return to base idle.

When I first went online weeks ago to Pa Performance’s website, the chat window appeared and I was asked if I had any questions. Over the next several days I had several minutes’ worth of conversation with this individual. S/he (how do you tell gender in a chat?) asked what my application was, and s/he expressed surprise: “Many people with 4 cylinder engines find they can’t run our higher-amp alternators, they are too much for the engines.” In the considerable amount of research I did going through pages and pages of old posts on NATO over the course of almost 20 years, no one that I could recall expressed that as a problem.

But, here it was. I bumped up the idle screw a turn or so, but that made only a little difference.

It’s been very hot here. I don’t have the time to mess with this…so I decided to put the other one back in. Fortunately, the only major changes I had to make were to get a new rectangular Output plug (I broke mine up trying to get the plug loose, finally just cutting the wires), which I did at Advance Auto. And I had to tape up the Stator wire from the new D-shaped Regulator plug that I had already bought for the new alternator. As it turned out, replacing both was not only necessary but would have been a good idea even if I had managed to save the original connectors—there was a lot of corrosion and nasty stuff in both sets of contacts.) I soldered the new Output plug to the Black/Orange wire. I completely removed the 4 gauge fused cable, as well as the two wires I had spliced in—taped those up (I also used heat shrink tubing as insulation on the ring connectors).

It was the Moment of Truth. I checked and re-checked to make certain all the modifications were reversed or, at least, disconnected. I reconnected the negative battery cable…then I started the car.

The Amp Gauge INSTANTLY sprung back to life (How does this even happen?). But, most importantly, it started right up with no issues. No stalling, no surging at idle—even with the A/C on! It ran as well as it has, pretty much, for years.

Numbers: 130 amp—Standing voltage before starting—12.76; on startup—14.47 volts, slowly dropping down. Previous one—Standing voltage—12.89; on startup—13.95, slowly climbing up to around 14.20.

EATC set on 72 (it’s roughly 97 in the garage, so I guess you could say it’s on HIGH); headlamps ON (with Fog Lights). 130—13.95; Previous one—13.49.

I won’t return the 130 amp one—at least, not yet. I’d still like to try and make it work, when the weather has cooled off enough to be bearable.

I had another chat on the Pa Performance site, with the same person (??) after the switch back. In part, I was advised as follows:

“You really need to drive it, all of this testing and symptoms on a new system in the garage at idle is a little misleading.”

“Your battery has never seen this much power and it all needs [is] to get to a new steady state, thus the alternator working hard and some of this.” [??]

“The ammeter will always have power but never swing as much as it used to.” (Actually that is NOT true. It doesn’t appear to have ANY power—it’s flatlined. Turns out the ammeter just wasn’t getting as much output with the 130 one, its moves would have been barely visible.)

Respectfully, if it hadn’t been 110+ for the past 20 days and broken that previous record (and killed at least 8 people), and I had nothing else to do, then yeah I’d do that—I might still, in the fall. But based on what I see with those numbers—I’m pretty happy with it. My windows don’t slow to a crawl going up and down with everything on; my lights are bright with or without a heavy load; and it runs great.

I hope this helps someone who is evaluating whether or not to go with the 130 amp alternator. I say, yes—go for it. But don’t be disappointed if it isn’t all that you expected. My car is in overall greatly shape, with some modifications and upgrades which have really improved electrical performance, as I mentioned—notably, the Fog Lamp relay project and replacing 99% of the incandescent lamps with LEDs.

As they say—YMMV.

Very odd indeed. Next time you have the 3g installed, see if disconnecting the output causes any difference. Don't really see how any more voltage/amps would cause issues like you are having. Does the 3g alternator spin relatively freely? Almost seems more like it's dragging so much that it's causing your issues? Not sure why the AC would cause issues starting since it doesn't kick on for a few seconds?

Good you are back to operating normally for now with the old alternator, I know how hot it's been... at least your not in Phoenix! Looks like only another day of 110+ here, although it's a little overcast today so maybe today!

I see you have a 87, that is a very poor design! I lost one 87 to an alternator fire and my current one I caught it with smoke billowing out coming from that stupid alternator pigtail.

At least you have the hard part done with getting the 3g to fit so swapping is pretty quick now. I would try to figure out what's wrong and get the 3g back in as soon as weather permits

I'm wondering if the wiring you did for the AMP gauge may be your issue? Maybe bypass that next time?

Amp gauge in any car is totally worthless IMO, especially in a TC where the gauge has NO ACTUAL NUMBERS, just the stupid hash marks. Volt gauge is MUCH MUCH MUCH more useful.

Does one hash mark up indicate charging at 5 amps, 20 amps or 50 amps??? Same for discharging!!

Had a factory amp gauge in my long gone 71 Tbird 429. It was just as worthless as the amp gauge in the TC.