Well recently my car has been dropping the voltage. While i drive the voltage drops from 14.0 to 12.9 to 10.9 as i see on the commander. Also when i drive it breaks up between 3500-4000 and kinda bogs and feels like it wont go. Im guessing the coil pack? Bad ground? But i redid the ground. Anyone with this problem please help. Thanks!

 

sounds like the alternators going bad!

 

brand new alternator

 

Did you check your ignitor pack? Also did you independantly check all your spark plug wires to check your coils. I have had 2 people in my local club of like 15 or so FD's who have friend ignition packs.

Alex

 

What are friend ignition packs?

 

Well there is an ignitor and there are ignition coils.

The coils or plug wires are good places to start looking when you get ignition breakup.

 

Would ignition breakup drop voltage?

 

No, but perhaps the other way around. Here are some other things to consider.
- Check that the alternator belt is not loose
- Could be a bad new alternator (it happened to me)
- The battery could be in very bad shape. It would probably be getting very hot.
- Loose electrical connection (you recently installed a new alternator, right?)

 

Yes brand new alternator Should i go take it to be tested? I think i hear the belt slip too.

 

tighten the belt to spec

 

RiON
Mine does the same thing. I been through most all of the grounds. The ground that is under the primary fuse panel is a very poor ground system and one of the two main chassis grounds; it goes through the relay / fuse panel mounting bracket and a small bolt to the fender liner. When I removed the bracket and bolt there was significant cathodic corrosion. Correcting this fixed most of the problem but at nite with lights on the car will start bucking at cruise throttle settings when the AC is switched on. Give it throttle and it will recover then at cruise again starts to buck again. Seems to be electical load related. It also took out my radar detector. As a note I believe the AIR pump clutch engages at cruise settings giving additional electrical load at miminal throttle settings and not during acceleration. The AC and AIR pump clutches are significant electricity suckers.

Question - Have you monitored voltage referenced from the engine block as a ground? I believe the ECM and Commander takes ground reference from the chassis. I'm curious if you get the same voltage drop from the engine block.

It appears to me that the electrical system needs additional attention to the grounds. The system should not fall below 12 volts if the battery is charged, at least until the battery discharges. So if the battery maintains 12 volts and you are measuring 10 there is either a bad gound or primary after the battery.

That's where I'm focusing.

 

bump

 

New alternator or not it sounds bad. Sounds like the regulator is bad. Being new shoudnt blind you from having a problem. Just bad luck. Hope this helps. G

 

regulator?

 

There is a voltage regulator built into the alternator that keeps the voltage regulated.

 

like everyone else said...get the alternator checked ...
i also have put on a bad alternator ,that was new...

 

Alternator was tested it passed. Changed the belt cause it might of been slipping.

 

how was the alternator tested...if by an autoparts store tester then I wouldn't trust the in car test. I did one on a alternator that was going bad and the tester said it was good, which was BS. I took it off the car and brought it in used the instore tester and the alternator failed the test. Now I'm not saying that the tester is wrong I'm just saying that it doesn't always work the best. Take it off and bring it in to get tested.

 

I tested my alternator w/ a bad regulator and it checked out ok too. Decided to have it ripped apart hence bad regulator. They can work intermittently for a long while before totally failing. Jumping through hoops is fun isnt it? It drove me crazy until we figured it out. G

 

I had the same issue. Turned out to be a bad optima battery. Do you have an optima battery by any chance? I swapped with a regular battery to test and all issues went away immediately.

Anthony

 

Like i said i took it to autozone to get tested and it passed. I bought it brand new from Malloy mazda should i ship it back and get another one? Im also thinking it could be my coil packs, because it idles like **** and the voltage drops and gets ignition break up. It stalls and bogs and hesitates between 2500-3500 so im guessin coil packs?