Oil Pressure Buzzer & Switches

[hiltow]

I think the issue here is more likely to be electrical, so posted under this category rather than 'engines'.

Car is a Mk2 1.6GT, which is currently still hibernating in the garage and wasn't used all that much last summer either. I store the fuel tank practically on empty, but to counter that I use when regularly starting the engine (and to keep the fuel fresh) I decided to put a gallon of new petrol in.

After I poured the petrol in, I went to turn on the ignition (but NOT start the car) just to see where the fuel gauge needle went to.

As soon as the ignition came on, the piezo warning buzzer came on - I presume the one associated with low oil pressure / impending engine failure. Turned off the ignition and switched it back on and the noise wasn't there. Obviously, this was a false warning as the engine hadn't (and wasn't going to be) been started up.

Presuming this is some sort of component failure / dodgy connection, though has anyone else had this problem? Reluctant to go poking 'round behind the dash without knowing what I should be looking for.

Keen to get this sorted, as I don't want a false alarm when I'm driving.

[ianaudia4]

Before you go digging behind the dash check the wiring that goes to the oil pressure switch. I have seen these fall apart due to age, easy fix, solder a new section in and heat shrink the connection.

The oil pressure switches can also fail, again an easy job to change and only cost a few quid.

[hiltow]

Cheers - I'll take a look at the wiring and the pressure switch.

If memory serves, the wiring consists of a single wire with a crimped spade connector on the end of it then slotted onto the sensor, but with a rubber shroud covering the connection.

All being well, I'll be at VW next weekend anyway, ordering a few bits and pieces, to get the car ready for use again, so I'll put a new sensor on my list.

[the edmundator]

The buzzer on my mars red GTI used to go off intermittently; it usually responded to a thump on the top of the dashboard.

[hiltow]

I'm trying to check the location of the oil pressure switch, but unfortunately Haynes doesn't mention where it is.

Car has the 1.6 EW carburettor engine. There is a sender switch screwed into the top of the oil filter housing, but there is another one screwed into the nearside-facing side of the cylinder head. Does anytone know which is the pressure switch?

Both are served by a single wire running to a copper female spade connector on the end, then shrounded in a rubber boot.

[ianaudia4]

The oil pressure switch is on the side of the head.

[hiltow]

Cheers, but just out of interest, what's the other switch on the oil filter housing for?

[mark1gls]

I thought that did the pressure as well as its a pressure sensor, I expect I could be wrong?

[PeteGLi]

Cheers, but just out of interest, what's the other switch on the oil filter housing for?

That is the high (1.8 bar) oil pressure switch. The one on the side of the cylinder head is the low (0.3 bar) oil pressure switch.

Check the FAQ's - http://sciroccoregisterforum.co.uk/faq/ ... ce-buzzer/

[hiltow]

I'm in the process of renewing both oil pressure sensors, but have a query about the low bar sensor that screws into the nearside face of the cylinder head. Basically, I need to know whether the one VW have given me is the right one for the job.

The original switch I took off the car is part No. 056 919 081 C and is rated for pressure 0.15 to 0.45 Bar (hence covering the crucial 0.3 bar setting, even giving earlier warning as it would activate at 0.45 bar). The colour of the cap is black.

The part VW have given me is 028 919 081 H and is rated 0.15 to 0.35 bar. The cap is blue. I'm just a bit worried that is isn't the right part because it would activate slightly later in an emergency at a lower pressure.

Car is a Mk2 1.6 carb with the EW engine.

You might have seen my post in the part numbers section, but I thought I'd try a different angle on this and ask what part others with this engine might have had recently from VW .

[jond]

i am having similar problems with the oil pressure buzzer,i have asked a mate who works at a motor factor to check the different sensors for me, he found 4 different ones two with a black cap for low pressure one blue cap for low pressure but slightly different bar pressure and one white cap for high pressure . i have fitted the blue one to the high pressure system on my car , so bought a white one and hopefully this should sort my problem of the buzzer coming on at over 2000rpm , why dont vw just fit one colour to high and low systems it would save a load of hassle

[mark1gls]

I've fitted a blue sensor to the side of the head and a white one to the oil filter, both are vw sensors and both have been fine for a couple of years on the DX engine golf.

[hiltow]

I've fitted a blue sensor to the side of the head and a white one to the oil filter, both are vw sensors and both have been fine for a couple of years on the DX engine golf.

These are the same colours as I've been given i.e. white for the high pressure (on the oil filter housing) and blue for the low pressure (on the cylinder head).

The old high pressure sensor (which has been on the car since new) was rated as '1.6 - 2.0 bar'. The new one says '1.8 +/- 0.2', which is the same rating as the original, just written a different way. Fine.

The low pressure blue sensor is within the right range, but kicks in at 0.35 bar instead of the 0.45 bar stamped on the original. Negligible difference, but I would have thought it would have been exactly the same.

The VW parts guy went through the ETKA system quickly when I ordered it. VAGCAT online quotes the same part number as I've been given, but VAGCAT simply doesn't contain all the additional model info that the real ETKA does. Also, VAGCAT doesn't indicate what the (correct) superseded parts numbers are. I'm guessing it'll probably be alright, but you know when you've just got that nagging doubt......