[electronics people get in here] 0-5v in, adjusted 0-5v out?

[downtrail]

10Mm adapter with 10mm cut off your inlet pipe no good? Other tb too long?

[Celica RA45]

what engine mounts are you using try the sa63 and that will move the motor back more mines 30mm off the fire wall

[Roman]

Engine is as far back as you would want it to go.

Current plan is:

1. Order a new voltage regulator, reassemble and refit alternator.

2. See if that made any difference to idle etc

3. Install hks wizard box airflow meter / idle adjuster.

4. Fiddle with it till car idles better

5. Adjust maf signal at rpm thats pinking to reduce ignition timing

6. Hopefully problems sorted / probably not.

[Roman]

Sooooo I bought a new voltage regulator, and swapped it over and reinstalled and I'm still gettting 14.7 volts at the alternator during idle. Bugger.

 

What else could cause this?

 

There are two wires on the alternator plug that return a voltage, with the engine off one was 12.8 volts and the other 12.5. (Or something like that, but one was .3 volts less than the other anyway)

 

If the lower reading one was the voltage sense wire, could explain the overcharging? Possible broken/damaged wire still perhaps.

Or is there anything else in the alternator being worn out etc that could cause that problem?

 

I guess I'll need to try run an external voltage sense wire and see if anything changes.

[xsspeed]

Wait 14.7 across batt terminals when running is ok innit? I have 14.4 in my head as volts across terminals after I replaced broken alt in my corolla

[h4nd]

14.7 is marginally high, tricky to tell if it's faulty. 13.8 to 14.5 is the usual quoted range. I had a suzuki at 14.7, was good for jump starting diesels.

This is for SLA, but same chemistry. http://www.powerstream.com/SLA.htm

 

Whats the a.c. voltage with the engine running, lights on, lights off? 

[kpr]

run  the sense wire directly to the battery.  or even to the main battery wire on alternator.   see if your voltage drops.   going form your readings volt drop maybe the drama

 

as others say 14.7 isnt that bad. but is getting up there

[Spencer]

Yea factory sense wire should be close to the battery, is yours just looped to the output?

[Roman]

battery is in the boot but runs a dedicated sense wire all the wsy to the back.

ive got another battery exactly the same in the sw20 so will swap them over and see what happens. otherwise will run a seperate voltage sense wire and see if it helps.

thinking probably the battery now though as its been run completely flat a few times and left for a few days/weeks/forever/coupelife before realising.

[slacker.cam]

Unless the battery is completely poked then that shouldn't be the source of your woes. Still, it's easy to check I guess. Take the alternator out and have it tested would be my suggestion.

[h4nd]

Hi impedance (stuffed) battery would explain higher than usual volts. The alt supplies current (to a volt limit), but the battery isn't drawing as much as usual, so the volts on the Alt rise.

 

I'm told the new batteries with calcium (since 90's) take a slightly higher initial voltage to start soaking up current (charging).

[bigmatt4]

14.7 volts is completely normal 99% of new cars regulate at that some at 14.9 try leaving your engine running for 5 minutes or so to let the battery stablize and the voltage should drop to about 14.5 turn on the headlights wipers and stuff and it should maintain that voltage.

Calcium batteries require a minimum of 14.6 volts to charge and if they are flattend dead dead flat they need to go on a calcium pulse charger to recharge to 100% oterwise they only recharge to about 60% of there full potential.