Golf MK1 Cabrio (1.6 GL) - Rocker Cover earthing wire - To potentially resolve Oil Pressure Warning

Hi everyone,

I have a Golf MK1 Cabrio 1.6 GL with Carb.

I bought the car with the Oil Pressure Warning light flashing on the dash (comes on over 2000 rpm - buzzer has already been de-activated)

One of the common issues I've seen online is the location of the earthing cable on the rocker cover.

On mine I can only see one earthing wire, which goes from the rocker cover to the side of the carburetor… is this correct, or should I have a better earth to the bulk head / coil?

I'm just ticking options off before I remove the clocks and get them sent off for fixing.

I've already changed the sensors, changed oil filter, fuel pump, and correct oil….

Thanks

Darren

Have you used a mechanical gauge to verify that your pressures are correct.  

The Flashing light and Buzzer are the Low oil pressures at over 2000 rpm.  

Oil pump's have a by-pass that can fail and remain open.
or closed.

With out checking the basics, throwing senders and things is a waist of time and monies.

When I bought the car, the previous owner promised he'd done an oil pressure check… and all was fine, and said he'd actually been driving the car for some years with the flashing oil pressure warning light on the dash.

The car is going into the garage in early Feb, to pressure check (for my own piece of mind) and swap in a new Febi oil pump, new oil, genuine VW filter etc…. I've only changed the sensors so far (still showing warning light), and as the post indicates…. I'm just wanting to rule out an earthing issue… as I've only got the single earth wire from rocker to carb… do I need something more substantial to the bulk head or coil?

Any ideas or advice welcome…..

(PS - I have a habit of throwing money at cars… for apparently no reason :-)  !)

When changing over the oil pump you may want to consider upgrading it to the 2.0L pump, on the 1.8 it is a direct swap, save for the bolts on earlier 1.8's and the pick-up tube from your old one that you swap over.
It has taller gears and gives better pressures.  

Earlier than 91.5 and you will need longer bolts to bolt it to the engine, as the earlier ones have a shorter bolt.
I can't remember the lengths. But the pick-up tubes on the 2.0 pump will not allow the oil pan to bolt up.  

The DPWS warning system is inside of the speedometer, and if he disabled the buzzer, chances are that he dinked things up.  It is there for a reason.  



pn 321 919 064

I would first suggest doing the Quick test to verify that your main battery to frame and frame to engine grounds are good.

https://www.volkswagenownersclub.com/threads/brianos-quick-grounds-test.134637/

Yes there should be a Bonding wire from the right rear valve cover nut to the Coil Bracket bolt.  If you are adding a wire use a stranded and not a solid wire with enough slack so it will flex with engine torque.

Thanks Briano1234!

Mine is a 1.6 so not sure I can upgrade the oil pump to a 2.0…. plus I've already spent the money on a new Febi Pump.

I'll take a look at the earthing point from rocker to coil…. I defo only have a thin wire between rocker and a bolt on the carb…

Who knows… maybe a new substantial cable from rocker to coil bolt will make a difference…. worth a try!

Thanks

Darren

Constant flashing and oil buzzer can be due to failure of the one transistor on the buzzer board, that was the issue with mine.

Is the board on the inside of the speedo.  I would imagine that the PO cut the wire to feed the buzzer, and that the issue if all the static tests say you have good pressures, then the issue is that board. or the wires feeding it.

Is that part of the board replaceable, or does it need to be fixed by a competent repair service…… or is it simply… new clocks required?

The transistor can be replaced. When it fails it is basically always on, so as soon as the board gets power, light and buzzer comes on.
I took the number off the old one and found one on ebay. The hardest bit was getting the board out!

The other issue I had was making sure the transistor was orientated the right way as documentation was non-existent. I make a guess and got it wrong, had to take the board out again. When I did it the second time I assembled it as losely as I could to connect it and test.
If you can find an old school TV repair place, they would probably be able to source and fit the part.

For ref, this is what my board looked like. I think the one Briano1234 posted is a later version. Same components just laid out differently.
Transistor is circled.