964 died on bypass! FFS

[MarkGolf]

Hi All,

Driving along in my 964, noticed that my radio had turned off and I could barely see the digital display on the gauge, so potential power issue happening, slowed down for a set of lights, noticed that the car was misfiring. Pulled away and then silence, car was dead and wouldn't restart, bollocks.
Had to push the car into the middle reservation of the bypass with idiots beeping me. Had a bunch of roofers ask if I needed a hand but I was done by then, thanks to them anyway. So, I checked battery connections, swapped DME, checked fuses, poked about in the engine, just making sure nothing weird has happened blah blah, but nothing had, tried starting loads of time but nothing, lights on the dash but no starter solenoid clonk or anything..

Called out my old man as I was just 2 minutes away from him, tried jump cables but no luck.

Manged to push the car to a safer spot and called the RAC, plugged his booster on and the car fired up better than ever. Removed the booster, wouldn't start..

Ok, I may have killed the battery by trying to start it X times. I have a battery isolator on the car, the battery is disconnected every time I finish with the car. He suspected it could be that causing an issue (is a cheap ebay thing), removed it and tried to start car again but no good.

Got the car running again with the booster, he tested the alternator output while the car was being revved, 13.3v was max output.

So, I need to pretty much charge my battery and do a few load tests to see if it's knackered or if the alternator is duff. The alternator was a refurb part, just before I bought the car, I haven't done more than 1000 miles since.

I have no idea what was refurbished inside it, the old voltage regulator may have been used for all I know. But, with the RAC booster on the car, the car just felt so much nicer to drive, I felt like the gears changed faster (tiptronic) , the revs didn't drop and it just felt like it wanted to go, like a sport mode, felt sharp. As soon as the booster was disconnected and I moved the car, it felt lethargic.

Any tips on things that fail or areas to check? 13.3 sounds low to me but for all I know, might be normal on the 964. Bad earth, which one?

I have left the battery on a CTEK charger over night and I'll see how the car behaves, any further help would be appreciated.

I was fortunate enough not to have taken my 1 year old out with me like I was about to, I really can't have the car letting me down like that with him in it.

Cheers!

 

[Zingari]

How old is the earth strap to the battery and also to the starter motor?

I had a total 'power out' which included the clock stopping and narrowed it down to a weak battery earth strap! As you're getting dash lights yours might be something else.

 

[dt4]

I got stranded on the outside lane of the M1 when taking my daughters car down to Uni for her
Came to a stop in a build up of traffic and it stalled and wouldn't start again
Very scary being stuck there once the traffic got moving again, luckily a bloke pulled up and another guy stopped in the middle lane and we were able to push it on to the hard shoulder, that turned out to be a straight forward knackered battery

A very similar thing happened to a friend when the alternator belt snapped!

 

[berni29]

Hi

These cars do not take well to a weak battery, and along with the 993 seem to kill them quite regularly.

Best of luck

Berni

 

[jkeith]

I had a similar experience. Keep my 3.2 on a trickle charger, couldn't understand why it wouldn't start.

The battery wouldn't hold a charge. Got a new one, problem solved.

Sometimes the obvious is too simple.

Cheers, Keith.

 

[markg59]

Had a not that dissimilar experience a few years ago. Driving my eldest from Newcastle to Manchester airport, dropping down from Saddleworth on the M62/M60, the dash lights faded, radio packed up, indicators stopped working... Eventually engine stuttered, gave up and I drifted into the hard shoulder. Panic call to taxi company so that my daughter could get to the airport. Eventual trip back home on the back of a lo-loader.

Turned out to be a failed alternator.

You said you tried starting it a few times, was there enough juice to turn the engine or was it (like me) just a simple "click"? Actually from what I can recall, I don't think it even managed a "click"!

Mark

 

[Stimpy]

13.3 is weak. You should see around mid 14v...

I'd see if the battery will take charge first then retest, if not replace it then retest, if not alternator....

As above, poor earths can cause lots of issues also.

Goodluck! :thumb:

 

[MarkGolf]

Thanks for the advice guys!

Earth straps are an unknown to be honest, I imagine they are original, if replaced, a long time along, they look in fair condition. The front one anyway, can't see any issues with that, the rear one, I can only see the terminal which mounts to the car and that has the green corrosion crap on it, so I will try and access that and clean it up, along with the other end on the gearbox/engine side.

Belts are in good shape and feel well tensioned, one of the first things I checked, just in case I had a snap!

I suspect the battery, it was replaced when I had the bodywork done and pretty much always been disconnected when not in use.

When trying to start, I was getting nothing, in the past, I did suspect my starter motor as a potential issue as I would just hear the solenoid click and after a few attempts, it would start but part of me now wonders if this was to do with a battery not hold good charge.

So I will check the battery as it has been on charge since Tuesday night, clean the rear main earth point and then test voltages and resistance.

If no good, I have a good spare battery to try and if that fails, alternator!

Sounds like a plan, thanks guys! :thumb: :thumb:

 

[Zingari]

For the money it's worth replacing the earth strap to the battery as well. Mine looked OK, until you untwisted it, but was the root of the problem for me.

Best of luck.

PS. Can't remember is yours a 'Auto'? Could it be something to do with the shifter microswitch not being exactly in P or N :?:

 

[MarkGolf]

I will certainly do that, might as well for piece of mind.

It is a tip (Shhhh), I did think that and at the time, was double checking that the indicator on the dial was matching up with the selector. Used to have a Volvo where that was a problem. :thumb:

Cheers!

 

[MarkGolf]

Hi All,

Just wanted to update this, investigated voltages etc, please see my findings below;

Checked earths, removed them, inspected, cleaned, the front battery one was perfect, the one from engine was in need of a clean.

CTEK charger removed, car not started = 13.31v, waited a few mins and this settled and remained at 12.98 each time I checked over 25 mins, only bonnet LED on and alarm LED.

Cranking = lowest I saw on my meter was 11.8v

Here is the weird thing;
At idle circa 950-1050 rpm = 12.12v

As soon as I touched the throttle, it went to 13.8v

Reving to 4000rpm 13.8v

Car off, battery showing 13.3v

I later fired the car up, it did the 12.2v thing again and my ABS light was on, the ABS light does show up and now I think it shows when it only registers 12.2v, it always turns off when I rev it, so it is coming on due to low voltage.

Why would the car remain at 12.2 until I rev it, as if something is sticking or engaging. Would this be a dodgy voltage reg?

Cheers

 

[ras62]

Its quite common Mark. I've seen new refurb alternators not supplying the correct charge at idle and then perfect 50rpm above idle. It took 3 different alternators before a mate got one for his turbo that worked on idle.
Good news is you have likely found the problem!

 

[g7jhp]

Symptoms sound like a failed alternator to me.

Not charging the battery, so the you are OK to start the car and then battery, lights etc fail and you come to a standstill. Happened to me in a 3.2 Carrera on the M25.

 

[coullstar]

Voltage regulator not correct one? I had a car recently that was similar.