The infamous capacitor discussion

[LongThrow]

Sounds like grounding issue somewhere. Also 1/0 welding wire is cheap on wireandsupply.com.

Grounding issue somewhere - I KNOW FOR A FACT It's not my amps ground, or headunit ground. How would I go about tracking ground issue? NYTHING with a ground, can cause this? Fuel pump, starter, etc?

 

[fatboytyler]

I've done much research on this (as far as google goes) and I have never so many mixed reviews on the necessity of this in my life.
I'll start with my problem.

all my equipment is in my sig, but for the lazy scrollers, 94 ford explorer - normal battery from autozone - brand new 95 amp (same rating as the stock alternator) alternator which is specfically for this vehicle. 4 guage KnuConceptz wiring. 500w sub amp wired to 2 ohm. Tested battery at autozone, it's fine. Alternator is fine. Wiring and connections are secure. Fuses are fused properly. Ground is clear of paint and is perfect. Tested battery again with DMM, showing 12.89 at idle with car off. Car running at idle shows 14.34. However, every now and then, when my car is at a stop light, I'll have 2-4v voltage drops. I'll turn my stereo off, still having dips in the voltage. This is only when stopped, while driving is fine.

was told a capacitor would fix my problem, no more than a 1.0 would be needed. is 500w + the 150w of my door speaker amp = 650w of power be too much on my stock system? Have not done big 3 uprade was told it was unnecessary for the entry-level equipment I have.

I'm wearing a fireman suit so I don't get burned by the flames I'm about to encounter.

Just as an FYI, I did not read 4 pages of this...

Sounds to me like your alternator. My engine drops RPM low enough to cause the alternator's regulator to stop firing, so a lot of times at stop lights my alternator essentially stops charging my vehicle. This could be the culprit or something similar. As for the Big 3, I always recommend it. It will help with the overall electrical flow of the vehicle, BUT it is not needed.

 

[Tripn88]

I'd invest in the big 3 or at least clean your three main grounding points. Battery to frame. Engine to frame. Also check alt to the bracket to engine. Check the pos wires from salt to.battery also.

 

[LongThrow]

Just as an FYI, I did not read 4 pages of this...
Sounds to me like your alternator. My engine drops RPM low enough to cause the alternator's regulator to stop firing, so a lot of times at stop lights my alternator essentially stops charging my vehicle. This could be the culprit or something similar. As for the Big 3, I always recommend it. It will help with the overall electrical flow of the vehicle, BUT it is not needed.

Replaced alternator, only rated at 95 amp. Maybe not high enough output?

I'd invest in the big 3 or at least clean your three main grounding points. Battery to frame. Engine to frame. Also check alt to the bracket to engine. Check the pos wires from salt to.battery also.

Going to do Big 3 asap, see if it helps. Cleaning battery terminals, and I'll hunt down all those wires. God help me. 1st gen explorers, atleast the 1994, have TERRIBLE hand room under the hood. And under the truck.

 

[fatboytyler]

Replaced alternator, only rated at 95 amp. Maybe not high enough output?
Going to do Big 3 asap, see if it helps. Cleaning battery terminals, and I'll hunt down all those wires. God help me. 1st gen explorers, atleast the 1994, have TERRIBLE hand room under the hood. And under the truck.

Brand new things can be made with defect parts. Even the highest of high quality products have brand new things go bad immediately. But it could also have something to do with your engine not keeping enough RPM at idle. Could be that you have an ECU that's going bad. The fact that it drops at idle with or without the system leads me to believe these things. Its plenty of output power for that kind of system. I ran ~1200 watts to my subs and ~300 watts to my doors on my stock 100A alternator and a Group 27 lead acid with very few problems.

 

[LongThrow]

Brand new things can be made with defect parts. Even the highest of high quality products have brand new things go bad immediately. But it could also have something to do with your engine not keeping enough RPM at idle. Could be that you have an ECU that's going bad. The fact that it drops at idle with or without the system leads me to believe these things. Its plenty of output power for that kind of system. I ran ~1200 watts to my subs and ~300 watts to my doors on my stock 100A alternator and a Group 27 lead acid with very few problems.

Very true, I had them load test the alt back to back. They got pissy with me the 3rd test, and I straight up flipped out on them at autozone because I have a 3 year warranty and told them while it works here in the store, cold, it won't work hot as **** under a hood driving 65mph all day, every day. Turns out it tested fine.

 

[big scott]

Charging System Basics

yup, thats what i was going to say.

been working on cars all my life..

doing this on a 1950 car can and will fry the alt.

so in saying that..................

DONT DO IT.

and can damage...

dist.

coil

module

and...

ecm. / prom chip.

 

[dev199505]

Very true, I had them load test the alt back to back. They got pissy with me the 3rd test, and I straight up flipped out on them at autozone because I have a 3 year warranty and told them while it works here in the store, cold, it won't work hot as **** under a hood driving 65mph all day, every day. Turns out it tested fine.

Even though the alt is new I would still get one from a different company autozone alts tend to fail quickly I've known lot of people thatll buy one and fail with in a couple months they'd get the replacement and the same thing would happen so they'd get a refund and get one from O'Riley or NAPA and it'd be fine

Sent from my HUAWEI Y536A1 using Tapatalk

 

[los33]

Even though the alt is new I would still get one from a different company autozone alts tend to fail quickly I've known lot of people thatll buy one and fail with in a couple months they'd get the replacement and the same thing would happen so they'd get a refund and get one from O'Riley or NAPA and it'd be fine
Sent from my HUAWEI Y536A1 using Tapatalk

Autozone is known to sell everything remanufactured.

Oreily and advance auto have new from denso and ultima

Sent from my draconis using Tapatalk

 

[ummduh 10+ year member]

Having a bit of experience with that vehicle, I'd start with the alt charge wire. There is a fusible link on that by the starter solenoid. The fuisble link can fail partially. I'd probably start by just bypassing that wire all together with a big 3 style 4GA + fuse. You shouldn't be having random voltage drops on that truck, there's practically no electrical load in it. No electric fans.. Just a fuel pump, EFI and your a/c fan really. You've either got bad electrical connections, or...

Second, stop buying electronic parts from autozone. My rule of thumb is unless it's a name brand that you can also buy elsewhere, and brand new, don't go to autozone for it. Don't trust any of their store brand junk.

Third, you can retrofit a 130A alt from a 97+ F150 with the 4.2l V6, it's a direct bolt on.

 

[n2audio 5,000+ posts]

FWIW - when it comes to rebuilt electrical components (alternators/starters) it is WELL known in the industry that what qualifies as a "rebuild" can be VERY minimal.

There is thread after thread across the various automotive forums of people having to buy 2 or 3 "rebuilt" replacements to finally get a good one.