voltage stabiliser?

Posted: Fri May 16, 2014 8:30 pm

Ok all you Audi experts, I'm on the scrounge again for your advice and guidance

Recently purchased a high miler Coupe Quattro , 1985, 171700miles, and its just passed its MOT if you were wondering. Goes very well....so far!

However, one niggling problem is that the water temperature gauge never gets past the 'C' mark whilst the fuel gauge will only read up to about two thirds full when the tank is in fact completely full up. I'm suspecting the voltage stabiliser as it has a common link to the two instruments.....but I'd appreciate any other opinions. Incidentally, the cars fan runs when the engine is idling so it IS getting hot and I have replaced the temperature sender on the block.

Central locking is an issue for another day!! Rolling Eyes

Site Moderator Joined: Jan 31, 2003 Posts: 9144

sounds like the stabiliser.

The KV Coupe quattros do tend to run hot. Mine always did

Posted: Sat May 17, 2014 7:48 pm

Thanks for that Mike, at least the local Audi garage reckons they can supply a suitable part, so we will see. Getting very hard to find most of the Coupe bits, more especially as some of them seem to be shared with the UR quattro.
I saw an earlier remark of yours about pouring money into the cars....I'm beginning to agree with you , but have to offset it with the excuse..."it's a harmless hobby" !!
best wishes, Smile

Posted: Thu May 22, 2014 3:35 pm

Cam belt and tensioner just replaced along with water pump and thermostat. Also now done the Voltage stabiliser , plus the smaller water temperature sender just above the thermostat housing.....and still not getting correct indications of temperature on the gauge. Also fuel indications way too low for amount of fuel in tank ( almost full in reality ) Where to go next?
I suppose the whole of the dashboard printed circuit could be suspect? Any other ideas from the learned ones please ?

Posted: Wed Jun 11, 2014 9:01 pm

Just in case anyone has any new ideas..... the water temperature gauge is driving me nuts....it certainly is registering , but the pointer never gets anywhere near the middle of the scale, even though I know the engine is fully warmed up, even to the point where the fan kicks in. Max deflection of the pointer is about a quarter of the way up from the bottom. So any bright ideas please ?
Water pump replaced, thermostat replaced, temperature sender replaced, voltage stabiliser replaced. Anyone got an old mark 2 audi 80 instrument cluster as I'm now down to thinking it is the gauge itself ?

Good news was the central locking problem turned out to be a broken wire in the harness where it goes through the door into the car interior , just for the record.

Audi Nut Joined: Mar 22, 2003 Posts: 93 Location: UK

My 80 quattro's dash does something similar to this but intermittently - from time to time the temp & fuel gauges both sink down, but both return to normal after switching it off & on again. Presumably it's a bad connection somewhere but is very hard to trace as it immediately cures itself. Have you checked all the dash connectors?

Posted: Sun Jun 15, 2014 7:45 am

Thanks for the reply and ideas.

Over the years of owning Audis of one sort and another, water temp gauges and their indications have been one of the most common recurring problems I've experienced from way back in the mid '80's to recent A4 Avant TDI 3.0

Variety of reasons but the older ones did seem to suffer with a breakdown of solder on the printed circuit. However, this Audi has a plastic sheet printed circuit as I'm sure you know, and not being very electrically skilled, not too sure how one tests resistors, and continuity of these printed circuit sheets. The problem with your car does sound like a poor connection from the ignition supply though.

Ah, the delights of old cars eh?