[Traidmarx]

i've had the issue since i bought the car just curious if anyone has had a similar problem. But the voltage is weird like if my windows are rolled up and i hit the button to roll them up again the voltage needle will drop waaaay down, the interior lights and headlights will also dim. It does the same thing with the windows down and rolling them down more. Sometimes if i have the bass turned up, the needle will fluctuate, other times i can just be sitting at a stop light or something and it'll drop down and the lights will dim, then as soon as i tap the gas pedal the needle shoots right back to the middle of normal. and the lights brighten back up. Any ideas?? I've had the alternator tested twice both times they said it was good, and the battery is about 2 months old.

[1fst5.0]

check ur alternator ur self with a DVOM. make sure u have ar least 13volts with all ur ususal electric accessories on. also make sure ur alt. connections r good, tight and clean. check ur battery cables too

[Traidmarx]

k i'll check it

[R0B0T]

i believe the ford alternators only put out a full charge at around 900 - 1000 rpms with stock pullies...

you're drawing too many amps when it does that, but if it doesn't kill the car i wouldnt quite worry about it unless you spend a long time idling, then you might need to give the gas pedal a love tap every now and then.

correct me if i'm wrong about the alternator...

[Traidmarx]

yea i mean its never been a big issue or anything just something i was wondering about.

[1slo5.0]

Originally Posted by Traidmarx i've had the issue since i bought the car just curious if anyone has had a similar problem. But the voltage is weird like if my windows are rolled up and i hit the button to roll them up again the voltage needle will drop waaaay down, the interior lights and headlights will also dim. It does the same thing with the windows down and rolling them down more. Sometimes if i have the bass turned up, the needle will fluctuate, other times i can just be sitting at a stop light or something and it'll drop down and the lights will dim, then as soon as i tap the gas pedal the needle shoots right back to the middle of normal. and the lights brighten back up. Any ideas?? I've had the alternator tested twice both times they said it was good, and the battery is about 2 months old.

The issue with the window switch is normal because there is an increased load on the circuit due to the window not being able to travel anymore. Every car does that. If you have an amp your bass problem is normal as well. If you have underdrive pulleys it will complicate things a bit more because the alternator won't spin fast enough at idle.

[Traidmarx]

i don't have an aftermarket am i have the mach 460 system but not sure that would cause the voltage to fluctuate, and i don't have underdrive pulley's as far as i know. then again not sure how i could tell at this point.

[nolife]

Like stated above, some fluctuation is normal. Larger than normal fluctuations are usually caused by a weak battery or bad battery cables/terminals. The alternator should put out about 13.8 volts. The fluctuating you see with big loads or quick large surges is the alternator getting loaded down until the voltage gets to the same level as the battery voltage. If your battery voltage is low because it is going bad or the terminals are dirty, the difference between the battery voltage and the alternator output are greater and the fluctuations are larger.

[JonnyB]

That sucks man. Wish I could help but im in the same boat your in. Im gonna check for a bad ground this weekend in hopes thats the prob. Anyway good luck gettin it worked out.

[Traidmarx]

another thing i get is engine noise through my radio...but it comes and goes its weird.

[1slo5.0]

Originally Posted by Traidmarx another thing i get is engine noise through my radio...but it comes and goes its weird.

Now that is not normal. That could be an alternator issue.

[95StangMX]

engine noise "usually" comes from having a power cable too close to your rca cables or a power cable too close to speaker cables. TM I am betting you have pullies on that car I remember when you bought it you said it seemed a little faster than normal I bet it has a few things done and pullies are one of them.....the window thing is pretty normal but it shouldnt drop TOO far.

[88Saleen]

i notice the same thing, and its because of the underdrive pullies. and, i have the same radio noise, but i just put in a CD and it all goes away. i think it might have something to do with possible spark plug wires. also could be from alternator, i never thought about it.

[Traidmarx]

Originally Posted by 95StangMX engine noise "usually" comes from having a power cable too close to your rca cables or a power cable too close to speaker cables. TM I am betting you have pullies on that car I remember when you bought it you said it seemed a little faster than normal I bet it has a few things done and pullies are one of them.....the window thing is pretty normal but it shouldnt drop TOO far.

i've got a video of it i'll post up tomorrow morning, it'll sometimes only drop down like like to the O in NORMAL sometimes it'll drop all the way to the N or a lilttle past it. How would i tell if i have pulley's on the car??? i don't see anything written on them. something else i've noticed and maybe this could be something else with the pullley's the temp gauge always reads a little warm...not overheating by any means but sometimes it'll travel on up to the A of NORMAL..could this be another thing caused by pulley's with the different pulley on the water pump. But i mean i guess pulley's are a possibility everyone that rode in or drove my car said it rev'd fast for a stock 5 liter

[1fst5.0]

the buzzing noise can be taken care with a noise filter. check ur voltage at the alternator, then at ur battery. also rev ur motor to about 1500 rpm while ur checking.

[baine21225]

i dont mean to thread jack buuuuut, since were on a voltage thread i just want to slip in one question. about a week ago my cars volts were jumping from about 14/14.5 (normal) up to like 17ish for a bit, but if i took it out of gear for a minute it would drop back down, then if it got reved past 3k it would go back up again etc.....new cables, optima battery, is it my alt taking a crap? i think its prbly the stocker....i have a 3g waiting to go on it just looks like a pita with the vortech on there

[flattusmaximus78]

2 bolts baine and that alternator is off. Don't sweat it bro.

[baine21225]

well then maybe i'll swap it over next week or so

[Traidmarx]

any ideas of how i can check to see if i have underdrive pulley's..??

[baine21225]

measure them?