Intermittent charging problem

[smurray]

Hi guys,

Looking for some advice on what I think is an alternator problem. Basically car was in the garage for thermostat and since it was in it has been having intermittent charging/alternator problems:

From startup everything electric runs slowly (wipers, windows etc). Only getting 11.7V but after a period of running (can vary from 2-5 minutes) it comes right and gets 14V. It is a very strange problem as I assume if the alternator was giving up it would under voltage the whole time?



As the thermostat is right behind the alternator and thus I think they have damaged something.


They say they didn't touch the alternator but found the plastic cap off the nut on the end of the alternator lying in the scuttle tray which leads me to believe they were mucking around with the alternator. Difficult situation as the last thing I want to do is to fork out for a new alternator because they have damaged my old one....

Any guidance would be very handy.

Cheers,
Simon

 

[Craig1.8t]

Not sure if this will lead you to your problem, but on the golfs the wires corrode (not that main fat wire the wires from the plug) check these and if you suspect the had the alternator off (in which i would take it off to do a thermostat to make much more room) check the 13mm bolt is nipped up tight, thats the basics.

 

[smurray]

Cheers Craig, going to have a look this weekend, can't understand why it only under voltage for the first couple of minutes then comes right, any one any thoughts on that?

 

[smokiedee]

i've been having a problem similar to yours funnily enough after a thermostat change but i know my alternator wasn't removed. could the coolant that came out from the thermostat have corroded my ground thats causing this? i don't have any starting issues just my amp on my boot has started going into protect mode but working normal, my hid's will randomly flicker then turn off and also my stereo will also turn off. sorry for the threadjack