Battery issues

[bluestreak56]

hes on about the black chunky braided one from the back corner of the head to one of the coil mounting bolts, can just see it here:
http://s110.photobucket.com/albums/n116/bluestreak56/?action=view&current=P1000578.jpg

edit: just out of interest which way did you go for PAS in there, TSR or Nissan? 

Thanks guys - all the work was actually done by the previous owner - he told me the PAS was a Nissan / Metro combo..

[bluestreak56]

Update on my issues

1) I finally managed to get the MFA working again after removing the fuse a few times.

However it seemed to work for one / two runs and now isnt updating as it was before just seems stuck until I switch between position 1 & 2 - even when I do switched it sits at a very similar level to what it was at before.

Havnt tried resetting it yet or removing the fuse again.

2) With regards to the battery - I left the car standing for 93 hours (everything switched off & stereo disconnected) it didnt go below 12.08v.

Anybody think the two issue could be related? Perhaps the relay for fuse 3 is on its way out? (If there is one)

3) The last issue I have is on cold starts. - When starting cold for the first 15/20 seconds the idle really struggles to keep the car going, generally I give it a little throttle to prevent it from cutting out but then its fine. This only happens on a cold start - as on a warm it travels straight to 850 revs and stays there.

Im going to get some stp injector fuel cleaner and see if that helps with this...

PS I get quite a tappety sound when Im giving it a bit of juice 3000 + revs is this normal for an old 16v?

Thanks all

[rubjonny]

1) fuse will work or it wont, I'd say its more likely an earth issue
2) battery sounds fine, but what was it under load (cranking)
3) swap the WUR, I had exactly this problem and another WUR fixed it.
edit: actually 850 is a bit low for a valver, raise it up to 1k

[Simon8v91]

Battery voltage of 12.08V sounds a bit low to me 

Have a read of this http://www.iol.ie/~kilkennyhockey/BentleyManual/EE01/ch4.1.2.html 

[bluestreak56]

Ordered a new WUR

Upped the Idle to 1000 revs

Removed fuse 3 last night after I drove the car (Voltage 12.53v) going to check it 24 hours later to see if its still draining...

[bluestreak56]

Right, update on my battery issue.

The battery is draining approximately 0.4v every day.

I have checked the current running through the circuit and the pull is 0.02mA (this is because I have removed the stereo)

I have added an extra earth on the negative battery post.

Reading about this issue - everyone states that if you have a parasitic drain then you should see an increase in current running through the circuit - but as mine sits as 0.02mA so this cant be true for my car?

I have tested both batteries and the old one even has held a charge above 12.63v for over 2 weeks while disconnected from the car.

So I can safely rule out -

Battery,
Alternator not charging (as it is),
Drain on Current,
Earth from battery
Anything being left on,

I'm at a loss now - if the battery is draining but theres no pull on the current then what could be causing the drain??  :?


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PS how can I test the alternator diode to see if its draining the battery while the car is off?

Thanks

[Ben Lessani]

to test for a parasitic drain get an ammeter (capable of 10a or more) and disconnect the +ve from the battery and bridge the ammeter in between battery +ve and +ve wire, it should be less than 0.07, although with an alarm a load of 0.1A can be tolerated. remove fuses one by one until the current drops to 0, then find what on that circuit is draining the battery. easy peasy.

happened on my car recently, and it turned out to be the parcel shelf covering the boot close switch, so the boot light was continuously on drawing 0.35a. your alternator is only for topping up a healthy battery, not charging it from being flat, if it ever goes flat, it needs charging properly. its also worth checking the levels in the battery and topping it up with some distilled water when charging.

Disconnect the +ve terminal, whilst having the multimeter set to I (current - a 10A setting should suffice), connect the +ve lead of the multimeter to the disconnected +ve lead from the car, and the -ve lead of the multimeter to the +ve battery post. That will give a readout in amps which will tell you the rough drain. It shouldn't be more than 0.05A (within reason), finding the parasitic drain is the main issue.

Finding a parasitic drain

[bluestreak56]

Yep - tried that watched the connection for over 2 minutes.

Rating of 0.02mA never went above that so I have no idea why its draining 

[Ben Lessani]

If its only 20 mAh, then its not draining clearly!

If the voltage on the battery is going down with only a 20 mAh draw, it sounds like the battery is dud.

[bluestreak56]

If its only 20 mAh, then its not draining clearly!

If the voltage on the battery is going down with only a 20 mAh draw, it sounds like the battery is dud.

The problem is the voltage is reducing by 0.4v a day so something is draining it 

I bought a new battery and charged the old one up and left it standing for 3 weeks - both hold their charge outside of the car but when in the vehicle both drain at a rate of 0.4v per day ..

The only other thing ive thought of since is to add petroleum to the positive connector (replaced the negative one with the new earth yesterday)