not strictly syncro related but on my mk2 16v I’m getting the oil light/buzzer combo in full force at the moment (constant buzz, light flashing red). What does that light actually mean? Oil pressure or oil quantity or what?
There seems to be plenty of oil in although when I checked (fresh after running) there were a few small bubbles on the dipstick. All oil (no cream cheese) but still like it had been foaming a bit. Any ideas what that might be?
Which sensor is it actually which control that buzzer – I had a cable failure recently and it’s possible this is just another old-wire-syndrome issue.
thx in advance 
It should indicate an oil pressure/pump failure (less than 3 or 5 psi iirc), but yes could be a wiring issue esp given the age of the wires/connections, do you have a seperate oil pressure readout? if not then it might be time to get one, poss something like this?
http://www.rimmerbros.co.uk/Item–i-RX1351-OIL?utm_source=froogle&utm_medium=feed
personally I have these
original post here
http://www.vwsyncro.co.uk/data/forums/topic.asp?TOPIC_ID=1877
hi Chris
no separate oil pressure readout at the moment, do you know which sensor I’m supposed to be checking? I’d guess the blue or yellow one before the filter. If so I’ve almost certainly got a spare sensor to swap and test.
The motor’s been doing *really* nicely recently snice the new head…it’s nearly perfect…just got the odd daft niggles like this from the age 
if it doesnt change when you swap the switches, then track the wires. if problem still is there, then try another speedometer (the oil pressure warning system is inside this, as a separte pcb
if its still going of, then it might be the oilpump
I forgot to mention that the blue oil pressure switch is activated when the pressure drops below 0.25 bar.
the other oil pressure switch for the oil warning light is activated at either 0.9 (Grey), 1.4 (black) ot 1.8 (white) bar depending which switch you have fitted.
btw are we talking 8 or 16 valve here? my reply was for an 8 valver, & then I thought about whats in your stable! [
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Ok well i did some more testing and as far as I can tell its the rear of the two sensors on the oil-filter mount which is at fault (or something in that chain).
As far as I know that’s the one whcih should alarm if there’s not enough pressure at 2800rpm or thereabouts and I was able to recreate the failure situation easily. I rev to 3k, trigger the buzzer and ease off, buzzer stays going. I do the same but then leg it to the front and touch the sensor wire to ground and the buzzer goes quiet.
Curently the behavious is the same whether I connect the sensor or not, with the same effect of going silent when touched to ground.
Sounds like the sensor right? ok so I managed to find 3 other similar sensors from other motors I’ve got kicking around and they all behaved the same way. Admittedly none of them are new so it’s possible they’re all dead but seems unlikely somehow… which has confused me.
Either way I’m gonna get a new pair of sensors from VW tomorrow hopefully and then we’ll see whether it’s actually the sensor or if there’s another issue in between.
As a precaution I’m also hopefully picking up a n electric pressure guauge which shoudl tell me if there’s a reading from the sensor… in which case maybe it’s the wiring or the dash cluster.
What I haven’t tested is putting a different sensor to ground and seeing if that does the same thing but I will tomorrow…
cheers for help so far all
ah and there was me wondering how it worked. That’s great and gives mr a plan which is independent of other people’s input which i like.
Good shout cheers
so – new sensors fitted but it still didn’t seem right, so i did a bit more digging online and found this page:
http://www.clubgti.com/FORUM/showthread.php?p=1130317
“Ok brief summary of how it works, the 1.8bar sender(white collar,yellow wire) this controls the buzzer the sender is normally open and when it gets the right pressure it shuts and grounds the wire stopping the buzzer going off, this circuit operates above 2krpm, if theirs a problem then the buzzer will come on and the led will flash. The other sender (black collar,blue wire) this controls the led, this senders normally closed, in normal operation you put ignition into the first position and the led flashes, when you start the car it should get the right pressure, the sender opens and breaks the circuit to the led and it goes out.”
What’s interesting is my sensors have always been connected the other way around… so white collar had blue wire, black collar had yellow wire. I’ve always faithfully put them back they way they were at the start but am wondering if that was wrong this whole time – can anyone confirm/deny the collars<->wires relationship?
The behaviour of the car seems more reasonable with the wires the way round they are in that post, but it means now my problem is flashing LED from/at idle, not warning buzzer at 3k rpm. It stutters rapidly at 900rpm and flashes steadily above that. Strangely no buzzer above 3k.
In any case have ordered a new oil pump to be on the safe side and postponed the door-fetching till next weekend…
Ah and the VDO oil pressure gauge I got to test needs a vdo sender so I guess
thanks for the help all
noo. don’t mistake the color on the collars its the writing on the nut-part that matters i’ve seen them in even same colors. but different trigger pressure