another voltage question

[tims 86]

i did the 130 amp pa performance alt and wire upgrade and also contour fan setup.. i have a up and down idle so i checked the voltage, with all things running at idle its 12.5-13.5.... at approx 1500rpm its steady 14.3 and the alt gets pretty hot.. is this normal? does this have anything to do with the idle surge? safe to leave it like this?

 

[jrichker]

Have you added the 4 gauge ground from the engine block to the common ground point on the inner fender yet? If not, do that before doing anything else.

Is this a singe wire alternator (1 big wire for alternator output) or does it use 1 big wire (alternator output) and the stock D shaped 3 wire plug?

Single wire alternators produce less voltage at idle than the stock 3 wire + altenator output wire.

You may want to have one of the auto parts stores bench test the alternator for you. It is free and can eliminate the alternator as being one of the problems.

 

[tims 86]

it has the plug and also the 4 wire, and yes i just added the ground but no differance.

 

[jamesburk3]

Did you ever solve this problem? Im running the same setup ,and my gauge lights and headlights dim at idle or on the road when i push a window switch down. It reads 14 volts at idle as well.

 

[stdyhand]

Did you ever solve this problem? Im running the same setup ,and my gauge lights and headlights dim at idle or on the road when i push a window switch down. It reads 14 volts at idle as well.

I upgraded to the 3G and have the same problem when I hit a window button. I installed the 4 gauge ground from the engine block to the firewall and from the negative terminal to the body. I thought a high amp alternator could handle the draw at idle and keep the lights brighter than the old stock alternator. But so far it acts just the same.

Also I did have my alternator tested at Autozone and they said it passed fine. I'm thinking about getting it tested again though to find out exactly what the voltage output is under load.

 

[jamesburk3]

I upgraded to the 3G and have the same problem when I hit a window button. I installed the 4 gauge ground from the engine block to the firewall and from the negative terminal to the body. I thought a high amp alternator could handle the draw at idle and keep the lights brighter than the old stock alternator. But so far it acts just the same.

same here, Cleaned up my grounds , ran an extra ground also and still having the problem. Im pretty sure my my stock alt wasnt doing this.

 

[jrichker]

Are you running an alternator from a 94-95 Mustang or a single wire alternator?

 

[whitey68]

HI,
Yes I do have 3g alternator fits same place for 89 mustang 5.0
1) I have remanufactured one wire or two wires
price is $115 include shipping and hanlding within USA
2) I have Brand new heavy duty alternator
one or two wires, price is $145 include shipping

Mounting you don't need to modify, and for plug
you need to cut the plug and hook up new plug
it comes with plug and instruction
in case if you need the two wires,
if it's one wire
just run 4 gauge wire from battery to the alternator


if you take my advise two wires is better than one wire
but it's up to you

this is from eagle auto electric, they sell on flebay. i think im going to order one his feed back is good, im going to ask him if there is any idle issues he knows of
whitey

 

[jrichker]

HI,
Yes I do have 3g alternator fits same place for 89 mustang 5.0
1) I have remanufactured one wire or two wires
price is $115 include shipping and hanlding within USA
2) I have Brand new heavy duty alternator
one or two wires, price is $145 include shipping

Mounting you don't need to modify, and for plug
you need to cut the plug and hook up new plug
it comes with plug and instruction
in case if you need the two wires,
if it's one wire
just run 4 gauge wire from battery to the alternator


if you take my advise two wires is better than one wire
but it's up to you

this is from eagle auto electric, they sell on flebay. i think im going to order one his feed back is good, im going to ask him if there is any idle issues he knows of
whitey

Buy it from a remote vendor and if you ever have problems, you have to take it off and send it back. Your car is down, you will have to pay shipping at least one way, and it's a headache to manage.

Buy the alternator from a local auto parts store with a lifetime warranty. If it breaks, you can take it back and get a new one, and test the new unit right there while you wait. When you walk out the door, you know it works correctly.

Two wire alternators work better at lower speeds than one wire alternators.
The mount modification is 10 minutes worth of work wit a dremel or a cutter bit in a drill. Don't be afraid of doing it.

Stangnet 3G install sticky http://www.stangnet.com/mustang-forums/646825-3g-alternator-install-how.html#post6673702 everything you need to know about 3G wiring.