UK-POLOS.NET - THE VW Polo Forum

Hi all, i hope one of you can offer some advice. I have a 2002 1.4 tdi polo and recently on a few occasions the car wouldn't start immediately after the car had been running? I thought battery on its way out but i haven't replaced it as yet as i wanted to avoid having to get battery and alternator without first seeking advice. On both occasions i have pulled over to answer a call (with the engine still running), then after about 5 minutes i notice the power steering light come on (and the power steering doesn't work. I used to have a skoda fabia that the power steering light came on randomly, and a restart would clear it), so i switched the engine off. Then when i try to restart the car it is completely dead, it doesn't even try to crank... I the radio still works and all internal and external lights work (i know lights etc draw less power than cranking, i just thought it was interesting to note that the battery musn't be completely dead). I then have to jump start the car and the car is fine after that and doesn't happen again for a few weeks? I just thought it was puzzling that the car is running, so presumably charging. Could it just be an intermittent bad earth or loose connection at the alternator end, is this a sign of a battery on its way out or failing alternator.

If it's relevant the daily commute to work is 75 mile round trip (mon - fri), so its not like the car has been stood over the weekend or anything.

thanks for looking at the post.

Leon

I think that you need to buy a cheap multi meter and check the voltage with the engine stopped and with the engine running - also check voltage drop between chassis and alternator body and battery + terminal and alternator O/P. The hardest bit, if you are considering the battery or the alternator are to blame, should really be to get the car started first thing in the morning, as your commute is a decent length the battery should be getting recharged well enough. Strange problem to accurately diagnose at length, sorry!

Edit:- after re-reading your posting, I think that you might find that the low current wire to the starter is fracturing - check the wiring on the starter solenoid, and remember to check that the "charge fail" warning light is lit until the engine is running as well as checking that the alternator is lifting the battery voltage up to 12.65 > at all times the engine is running, the higher the voltage the lower the state of charge of the battery must be as the alternator OP will get controlled to stop over charging the battery.