Beretta.net

thanks for the advice guys. the alternator looks pretty much new which probably doesnt mean much. however, if i were to inspect the wires, what would i be looking for other than an obvious disconnect?

also how tight should the belt be?

loose or broken wires. corrosion

That may be the case, but even when I used to cruise around in mine, right after I bought it from the dealer, it would occasionally drop below charge point at stop lights, etc.. Dealer could never find a problem, they figured some of that was due to the low idle. 4 alternators later, it still does this. Hotter it is, the worse it is, it will even stay low at speed. Been like that as long as I can remember. And, at odd times, the voltage will jump up higher and be fine for a while, then suddenly drop back down where it usually is, almost like a bad connection, but I never have found one. When its 50F or colder, it will be really high (like nearly the top of the gauge), then go a bit lower and seem to stay in a "normal" range. My thing is, if its not the alternator doing this with regards to temp, what else would be?

Just saying it sounds familar to what I have had for years.

My 88 3.1 i have changed 3 alt's on it. and the volts on the gauge stay about half all the time, doesnt seem to drain past that even with my red top in it.

The 96, if i have my A/C on and stereo cranked my amp will kick off. if im idling with just A/C on nothing else i can watch the gauge slowly dropping even down past half way. thats with my red top battery in it. i think the alt is just getting weak and i have a brand new one i can put in maybe over the weekend and see if that helps. i was going to do it the other day and i opened the hood and looked around and said forget it LOL, theres a cooler thing on it that runs back to the firewall and the power steering lines clip on the side and i just wasnt into all that in the dark.

my 96 Z came with a fairly new battery and seemed to drain down way too much so i put the red top in and it helped alot but if i have everything running the gauge will still drop but not as much.

SGR, poor grounds and broken wires under hood may cause problems with correct value of sensor signals feeding the ecu, and will cause performance problems.

i had similar problems on my Z26 but by the sounds of it not as bad..

I changed the alternator tonight and seems to charge higher and holds there better with stereo cranked and A/C on.

If i knew where the wire off the alt. went to i would replace it with some 4-8 gauge stereo power wire i have lots of various pieces laying around. but that wire on my Z runs up to the fire wall and runs through with all the other wires and not sure where it leads to.... The starter ? that would be a fairly long run of wire to run across the firewall then back to the front of the engine.

My 88 runs along the power steering pump/water pump ect right to the front, not to the back and up and over and down and crossed all over LOL

Usually you have seperate feeds for the alternator and the starter. The big three involve the rear main ground (or the transmission one, depending on who you ask), the alternator feed and the starter feed. It does not replace them, just supplements. The alternator one is tricky, as its a small mounting location. You have to be SURE that your feed will not touch anything but the mount, and also install FUSES on those feeds, that way if they do short, they won't cause a fire. Have to have a hefty fuse and fuse panel though, or use a fuseable link. Lots of amps go through those feeds.

Dtmace upgrade to the big 3 or run 4g back to the battery from the alternator.

Someday. May wait till I go 3400.

If you were closer id be in to help ya lol. i just had finished my 3500 swap a day before drag racing at bfest lol. Id try nd talk you into 3500 swapping but youd need a tuning device of some sort or know someone who coupd tune obd1

OBD1.5. Not worth fucking with in my opinion. Hence the reason for just dropping in a 3400. Simple and will run without having to do much.

Now later when I find a really nice OBDII 96 shell, then I will cause some mayhem. But that will be a few years away.

Your obd1.5? I thought 94 was obd1 idk lol. Nd yea i suppose you could do jons write up,convert 1.5 to 2. there a very clean one in south bend i thought about picking up, no moyor no trans 300 very clean base model. Its a 96 black rose metallic.

As I said, not worth it. 230k on the clock. It will be either a 3400 drop in or another 3100. Will keep the car going as long as I can till its either beyond fixing or I sell it, whichever comes first. Not going to be redoing a harness for an engine swap on this car.

update:

i did a full battery check and the alternator is new according to the seller i bought from. the gauges are still acting funny. any other ideas?

New alternator does not mean good. New what? OEM? Rebuild? Etc?

There are people on this board who have bought new (Or new rebuilds) of alternators and have them bad out of the box. You did check all the feeds? Make sure the ground going to the firewall from the engine was tight, one on the transmission was good, etc?