Joeypete

I currently have the base 108 amp alternator on my 90 Toronado. Because my car has the optional VIC, it puts a lot of strain on the charging system, especially now in the warmer months with the A/C running all the time. I was thinking of putting the 120 amp in it (it was optional for the car) and am wondering if I can use the same wiring? I assume it is the same, especially since after looking for replacements, most are the 120 amp anyhow.

I've never replaced an alternator before so I'm not that familiar with them. Any input would be greatly appreciated!

Thanks!

Olds64

It should be relatively easy to replace the alternator. If your Toronado is a daily driver that you do maintenance on I suggest buying a Chilton's guide. They aren't as good as the Factory Service Manual but they are invaluable for common maintenance items like alternators, brake master cylinders, fuel filters, etc.

The easiest way to tell if the high amp alternator would fit your current wiring harness is to look at one at the parts store. Just compare the two. If they have the same wiring harness plug you should be good. I don't know of any problems you would run into on that car.

Joeypete

Cool, thanks! I do have a GM manual for this car. It mentions the 120 amp but doesn't really say whether or not there is a difference in wiring. I guess I'll have to check a new one out.

henryk8398

You should do what Olds64 suggests, but most likely, the alternators will be the same as far as wiring. Should be plug and play within each series of alternators.

joe_padavano

I'm curious as to why you think the alternator requires an upgrade? Are there other symptoms? Chances are the brushes in the old alternator are wearing out. Of course, there's no harm in upgrading.

Olds64

You can always have the old alternator checked out at the auto parts store.

Joeypete

I think it's the original alternator and when I have the A/C on and stopped at a light or something, the volt gauge goes down into the orange...around 12V...so I figured it could probably use a boost since being in AZ, the air conditioning is on for about 9 months out of the year...lol.

Good idea...I will do that!

joe_padavano

Sounds like worn brushes in the alternator. You can certainly upgrade if you want, but a rebuilt stock unit will also work.

Joeypete

Excellent...any brands better than others?

jensenracing77

i would never get one from Advance Auto parts, they are junk. i have had good luck with Car Quest and Napa. if you go to Advance i would get the GM alternator and not the cheeper ones they offer.

Allan R

Joeypete,
What did you end up doing? BTW, I know this may be an after the fact post for you but it wouldn't be a bad idea to check your battery to see if its in good shape. I had a similar problem with my 98 and went through "hell" trying to find the problem. I found a weak alternator, new (defective battery) amongst other things, and finally found the source of the problem as a minor vacuum leak.

Also, if you are finding a drop in idle when you're running the AC, you should check your IAC to make sure it's not carboned up or not working. It is supposed to compensate for the AC with an increase in vacuum to allow your rpms to remain steady when the AC pump is cycling. An IAC is really cheap and easy to replace or clean.

Joeypete

Sweet thanks. I usually go to O'Reilly (Checker) and they stock Ultima and I can order Beck/Arnley (but it's about $50 more). You know anything about these brands?

Thanks Allan...I haven't done anything yet since I'm in the middle of my work week. Today it was getting weaker so I need to do something soon. This morning my taillights would not turn off...was kinda weird, though maybe unrelated. I pulled the fuse and put it back in and now it's ok...who knows.

I'll check the IAC as well...the car has pretty low miles so I imagine it's got a lot of original parts. I haven't really done much to it since I bought it except fix some pack rat damage and then the dealer did some work for me. I replaced the battery because the car died on me early on but then I discovered it was corroded battery cable terminals. I converted them to top post since the nut was stripped on the side terminal...so the battery is good.