A new alternator changed my idle, my fuel economy and....

Headlights to tailights and everything in between.

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ciper
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A new alternator changed my idle, my fuel economy and....

Post by ciper »

One night I was driving home when I realized I had forgot something at work. I pulled a quick u-turn (at full throttle) and experienced what felt like fuel cut (when the g-forces pull the gas away from the pump) except I had a near full tank. Strange.

Afterwards I started smelling the nastiest caustic smell. When I got to the office I could still smell it, so it must have been the car. I opened the hood and BOY did it smell. I looked around and didnt see anything strange so I thought maybe a bag got stuck to the CAT.

After coming back out I started the car and I could feel it was different. After driving I noticed the lights where getting dim and acceleration was hard.

Luckily Ive owned so many piece of crap cars I know what a bad alternator feels like. What I couldnt figure out is why it failed all of a sudden and had such a nasty smell.

I turned off my headlights whenever I could and tried not to use the brakes. Luckily I made it to kragen. Opened the hood and that same strong smell was there.

I spent a good hour and a half trying to connect the alternator to the testing station. It was to a point that the guys let me do it myself and I created my own custom wiring harness! They where afraid it might blow up so I operated the machine. It showed that everything was fine ?!

It was now 20 minutes after they had closed and I said flat out "Okay, Im dont messing around. I want to go home. Give me your employee discount and Ill just buy the new alternator, even if it isnt the problem"

After installing the new alternator I knew instantly that it was the culprit. The car ran great! I thought it was just that new parts feeling.

Now its been weeks later and the car is still better. From the top of my head:
Idle speed is not in spec (low end) dropping probably 100rpm
Radio engine noise is gone
More power
Consistant shifting from the transmission
Better ABS control (not as many random engaugements and better stopping power)

Because of this crapped out alternator it also screwed up my battery.

I suggest a modification (if you dont plan to get an ultima) would be DT-3 battery from Wal-Mart for 40$ It has both posts and side terminals. More power than stock too. The only issue is the leads need to be adjusted slightly to reach. The main positive to the fuse box on some cars is slightly too short so you have to loosen the mounting ring on near the battery terminal and point it towards the fuse box. Then on the bottom of the box cut a notch to allow more of the wire out. The cable that attaches to a bracket along with the cruise/throttle cable needs to be removed from the bracket and the main ground on the transmission needs to be loosened and pointed towards the battery.

The front terminals are great for attaching accessories.
eastbaysubaru
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Post by eastbaysubaru »

I noticed almost all of the same things you did ciper. I replaced my alternator about two years ago and the battery went shortly thereafter. I like the additional battery posts idea. I've got a few accessories as well and those would definitely come in handy.

-Brian
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Post by HomeSlice »

my alt died on me tonight i got it apart in the garage right now. im puttin a used one in. i hope i see some benifets and i hope my yellow top dont crap out cause of the alt,,,,,,,
MY93BC Legacy Sonora Sand---> black plasti-dip?
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Post by Legacy777 »

You can suck the yellow tops dead as a doornail and they'll be fine ;)

Been there done that....a couple times. I had my driving lights wired up and they stayed on even if the car is off. I've forgotten to shut them off a couple times and sucked the battery dead. I get a jump and everything's ok. It probably wouldn't hurt to put it on a trickle charge overnight though.

I've since wired the lights up with a relay so they go off when the acc power goes off.
Josh

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HomeSlice
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Post by HomeSlice »

sweet josh cause i was worried-----everything is great- so far- no more radio noise. which was driving me crazy- i thought it was the fosgate rcas- no more diming lights when the bass hits. i jus got a cap to help the draw. i already got zero gauge wire to the back. so i should be fine now.
ciper was right a hell of lot more pepy
MY93BC Legacy Sonora Sand---> black plasti-dip?
MY93GC Impreza Amethyst--> Glacier/aspen/pd White
93BC"edm" 93GC 90BC R.I.P.
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Post by Legacy777 »

yeah.....I felt a little difference with my HO one, but because I think I have the underdrive pulley and the output of the alternator is fluctuating a lot and possibly cutting off.....I don't think the ECU likes it too much.

I will hopefully be taking care of the issue shortly. Just got to wait for the parts from australia :)
Josh

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HomeSlice
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Post by HomeSlice »

damn josh quick response :D
what u waitng on from AU?
MY93BC Legacy Sonora Sand---> black plasti-dip?
MY93GC Impreza Amethyst--> Glacier/aspen/pd White
93BC"edm" 93GC 90BC R.I.P.
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Post by QuickDrive »

Out of curiousity. what would be the price on a new Alt???

Just curious as I've got radio noise right now, wierd blips and crackles and ground noise on the stock tapedeck and speakers.

Just wondering if I should get my alternator checked before I plop in my better stereo from my other car...
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Post by czo79 »

Yeh Josh...Do tell, is this the vaunted overdrive alternator pulley you've been mentioning? Any chance you could tell the rest of us how to get it? I get a little dimming on occasion from mine...I've thought about getting one, especially as I would like to upgrade my alternator to the one you got too....
thanks...
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Post by Legacy777 »

Yeah I'm waiting on the underdriven alternator pulley.

Gofastbits is the only company that makes an underdriven alternator pulley.

All the others are just normal size. However you really can't buy just the alternator pulley. I contacted gofastbits directly & asked them if there was a way to purchase it separately. They setup a special thing with autospeed and I'm ordering through their online webfront. I'm working on getting the details, color of pulley & shipping worked out.

Getting the underdriven alt pulley will help, however it still may not put me where I want, so I'm going to get aluminum stock sized crank pullies & PS pulley (while i'm at it) Larry at imprezars has the N1 pullies and said he'd sell me just the crank & PS.

So when I'm all done I'll have a GFB underdriven alt pulley, stock sized N1 crank & PS pullies.

When I get the pullies I'm going to take circumference measurements and work up the numbers on the rpms.

I also want to go to stock sized crank because I have been getting a weird vibration sometimes when turning my steering wheel under slow speeds. I have funny feeling it's because the PS system is not getting the pressure it needs since the crank pulley is underdriven. We'll see how that issue works out when I get done.

I'm probably going to do all the seals & timing belt when I do the pullies too.
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
FrmRgz2Rchz
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Post by FrmRgz2Rchz »

Legacy: could the weird vibration be do to a bad axle?
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Post by mTk »

Legacy777 wrote:I also want to go to stock sized crank because I have been getting a weird vibration sometimes when turning my steering wheel under slow speeds. I have funny feeling it's because the PS system is not getting the pressure it needs since the crank pulley is underdriven.
I've actually noticed this problem with my pulleys. Everything worked great w/ all three of them on, no dimming at idle, steering was fine. However when i mad the mistake of ramming the PS pulley onto my old style pump, it screwed up the splines inside the aluminum pulley. Once i got a new style PS pump and put on the GFB pulley, there was obvious wobble that began tearing up the belt and pulley.

I put the stock PS pulley back on, and i get what you have described above. It generally only happens before the engien has warmed up, but is definitely linked to steering.

MK
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Post by Legacy777 »

FrmRgz2Rchz, just changed the axles....that fixed a vibration issue I had at speed.


MK,

All I have on there is an underdrive crank pulley, everything else is stock. Only other issue I can think is the PS pump.....it was a used pump. My original was shot...bearings toasted.

The vibration I have usually happens when car is warmed up and I'm pulling in my driveway....however it's sort of random....I think it has a lot to do with the amount of assist.
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
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