HELP Hdi wont stop

[rd070707]

Okay guys so what do you think about that earth? I think it could be the culprit but when i go to undo the bolt it comes half way out then spins

[attachment=15424]

[rd070707]

Okay so since I attempted to disconnect that earth and had to stop because the bolt appeared to be spinning, the battery light has decided to randomly flash a few times when i started it. Im guessing this is gonna be my problem BUT..... should i reposition the earth as if i take the bolt out il never get it to tighten again.

[Toms306]

Is that the captive nut one or is there a nut on the otherside of the arch? I know theres a few nut/bolts that go right through.

[rd070707]

Voltage across the battery was 10.87v with engine running and lights and fans and rear heater on. Def not right

[Toms306]

Hmm, should be about 14v charging. I'm surprised you could even start it with less than 11v tbh.

Sounds as though the alternators dying, but the battery light should be on permanently if that was the case! Did you sort that earth point?

[rd070707]

So this bolt wont come out all the way? Do i cut it to release the two wires and earth them elsewhere?

[Poodle]

Is that the captive nut one or is there a nut on the otherside of the arch? I know theres a few nut/bolts that go right through.

[powerandtorque]

Sounds as though the alternators dying, but the battery light should be on permanently if that was the case! Did you sort that earth point?

In my experience, alternators can fail without the battery light coming on depending on what exactly on it has died.

[rd070707]

It doesnt go all the way through so i had to just cut the head off it and now im going to move it down a bit and clean up a patch for a new earth.

Once thats done if there is no difference i will be looking at the alternator although i cant see how it makes it keep running after you switch it off

[Poodle]

If it's not stopping on the key it's most likely down to a dirty or knackered regulator. If you're going to take it out and flush it then be VERY clean when you do so, no muck at all can get inside the pump.

[rd070707]

Okay guys, that earth is now sorted. Just removed the earth beside it and cleaned it up and earthed them there.

New negative battery terminal as well.

Battery was reading 12.08v before i connected it. Connected and turned on ignition, lights etc all normal.

Tried to start it and it just dies straight away. Tried twice and now the battery is at 11.8v and rising again.

I thought 12v would have been enough surely?

[rd070707]

Okay guys bare with me here, was just measuring lp pump voltage with the Ign on and loads of crap was going on.

Lights dimmed initially then the abs, ps and airbag lights all started flashing, relays were clicking like mad, blowers coming on and off etc. Voltage at lp pump was 6.5v and there was only 7.2v at the battery.

Considering it was 12v before i turned the ign on.

Heads fried lol

[powerandtorque]

12.08v is a discharged battery.

Should be 12.7v if it's fully charged, and as said before, should be 14.0-14.5v or so when the engine is running.

A flat battery will play havoc with the electrics on a 306 HDi in my experience, so I'm not surprised lights and flashing and relays are clicking away to themselves.

[rd070707]

Okay so battery needs charged, but why does the voltage drop to 7.2v with the ign on?

[powerandtorque]

Electrics trying to suck juice from the battery, battery can't give it as it's discharged, so the voltage plummets.

[rd070707]

Okay so got the battery charged, put it in started no problem. Immediately voltage had dropped to 11v and was plummiting all the way down to 8 odd volts. Now when i revved it the voltage seemed to rise again slightly and it went back up to 11v for a short while before falling again.

There was 1v less at the alternator than the battery. And when i turned the key off and it kept going the voltage in the battery and the alternator increased.

I assume i can take from this that the alternator is not charging? Or do i need to look at why the battery/ lift pump still have power after key off?

As always any help greatly appreciated

[cully]

charge the battery over night and get it to a garage who can test the battery
sound like the batterys fecked to me

but dont explain why the battery/ lift pump still have power after key off
have you checked the ign switch is working correctly?

[rd070707]

Battery is brand new cully

[cully]

disconect the alternator Main + terminal
the internal diodes may be shorted killing the battery

[rd070707]

So how do I cure that mate? Is this while running?

[cully]

dead alternator could drain battery without ign on

i still recon as said before ign switch

[rd070707]

I will have to get in behind and try find it. Is there no sure fire way you can test the alternator?

Even if it wasnt charging surely the battery wouldnt discharge that quick

[rd070707]

Just a thought the battery light flickered a few times when i first started it if that means anything

[rd070707]

Anyone any more ideas how i can be sure/ rule.out alternator failure?

[rd070707]

Alternator is being stripped off for testing at the minute. Gut tells me its not the issue but have to start somewhere

[rd070707]

http://www.306gti6.com/forum/showthread.php?id=132418

Just came across this, sounds very similar. I have checked that plug and it was corroded and i cleaned it out with contact cleaner but it maybe wasnt enough

[rd070707]

Update - new alternator solved the battery drain she is now getting a good 14.5v at the battery.

Still wont stop by the key though.

Ive tried a new brown relay and i tried pulling engine bay fuse 40 for the fan plug but to no avail.

[rd070707]

Okay in mega need of help now guys. Earth cable snapped today and it died. So new earth on and it runs but still wlnt stop by the key.

Ignition now smells burny ut cant see anything melted?

Car wont stop by pulling the battety either, only by the fuel pump plug

[cully]

change the ign switch!
ive said it before but you still have not touched it

[rd070707]

Okay will try get one here and see