Hi Guys,

I've got a Classic V3 Impreza. Up until recently its been working without fault.

But over the last few weeks, couple of months its developed a series of probelms which mya or may not be linked.

First off, the car was working fine. I was bought a grounding kit as a present so I fitted that with no problems, Car started and run fine, with a more stable idle so I actually thought it was better than before.

A few weeks later, I parked up after a short journey came back to it an hour or so later and it wouldn't start. It acted as though it was completely flat.

I strap some jumps leads on it and it started up fine. Albeit the voltmeter only showed 12-12.5v.

Seeing this I thought it was the Alternator. Instead of testing it I bought a 2nd hand one and bolt it on and the car started up fine and was back charging around the 14-14.4v.

A few days later I could get the car to open with my alarm fob, thinking the battery was flat I changed to the back up fob and the car worked fine. Although now I can't get the key fob to remember the frequency and I constantly have to reprogramme it. I've no idea if thats connected, but I thought I best mention it.

Five days again, I was driving along and I started to notice a high pitch wine coming from the engine bay. Listerning closely its the Alternator again. Although this time I tested it and its putting out the correct 14.4v.

That said with all the toys turned on, it dipped to 11.89v at idle. If I put my foot on the pedal it does go up but not to 14v. Previously I didn't have this problem. I actually had more Amps back then. I only have two at the moment.

Anyway, the belt was a bit worn so I've changed that and yet still I have this charging problem. I've tested the battery and it is holding more than 12v when the car is off, so I'm happy its not the battery.

Today, I drove to work which is about 4 miles. Parked up for 4hours or so, started the car up and drove about 1mile to the petrol station filled up went to start the car again and it was as though I had completely drained the car flat again.

A quick jump start and it started up again fine.

I was checking the Voltment all the time and it was putting out 14.4v.

I've noticed when the Air/Con is on the power dips dramatically but I beleive thats to be expected due to the power it demands. So I don't think its that.

I don't think anything is shorting out, as no fuses are being blown. A friend suggested it could be the immobilser. But I don't think its that as when it doesn't work its as though the car is flat, I don't even get iignition lights which I normally would do if the immobilser had kicked in.

Any idea? I'm going to a Auto eletrician on Thursday to have a look. But thought I best ask as I don't fancy having my pants pulled down on price if its just a dodge relay or something I could do.

 

OK, probably a daft question, but you HAVE checked the battery earth is tight and clean, haven't you?

Ditto battery +ve if it's been disturbed.

 

Smart alternators don't charge unless a decent load is present. When you run the car, put the fan on full and ther sidelights, but I would have thought the amps would have been enough.

Perhaps you need a monster alternator to cope with the power for the system ?

dunx

 

I don't think the size of the alternator is the problem, as I've been running my system for two years and its been fine.

I've not cleaned the terminal, but that said their not really dirty. But for a five minute job I'll wip the terminals off tomorrow and give them a clean.

 

Remove them earth straps & give it a try.If that works you know what the fault is.If you still want them on mybe put one on at a time & see which one is causing the fault.If you want to check the battery,charge it up then check the cells with a hydrometer & measure the specific gravity i think it should read about 1150, normally the hydrometer with have a green,amber & red patch anyway.Or just disconnect the battery & see if it still goes flat.

 

Another quick check to do when the fault happens : put the headlights on when trying to start it - if the lights go dim its a battery/charging/leak-off problem.
If they say bright but the engine will not crank over, then look at a starter/ignition switch/relay problem.

Mick

 

I've been out a bought a new gold plated earth terminal, I've disconnected the battery wetadry sanded the neg and postive poles, degreased them reconnected the terminals and finished it off with some vasoline to stop corrision. Its as good a connection as I can make it.

As a side note the earth connection on the battery was poor, so hopefully that was the problem.

So far so good, but as its an intermitant problem its had to say. I've got a mate coming over later with a multimeter and we're gonna test everything again and see what happens.

 

 

Sorted, bad ground at the battery was to blame.

I switched everything on last night, heater, aircon, stereo up to the max, lights the lot and the alternator was still pushing out 14.4v.

Strangely enough the whining noise from the alternator has gone too.

Cheers all.

 

Was my first thought: the whining noise from the alternator is it trying to work too hard to produce sufficient voltage/current to OVERCOME the bad connection.


Once saw a mini, who's owner, at college was crying: when he switched on his wipers, the indicators went, sounding the horn flashed the headlights, foot on brake pedal caused hazard to go. It refused to start, the starter motor just groaned over, no oomph.

ALL down to a poor battery earth connection: he bought my beer in the student union all night