Oil pressure

[batteryman]

Had the oil pressure light and buzzer coming on intermittently in my '87, T25, Transporter petrol so got a mechanic to replace both sensors. After he did this the oil pressure buzzer would come on all the time when revving the engine and go off at idle, which we both thought should be other way round and was different from the original fault when the buzzer would come on for a little while and then go out again. If I fiddle with the long,white plug connection on the back of the dash and set it in a position where the oil pressure light will flash (once only and then goes out) on start up everything is fine, but from what I understand the oil pressure light should flash more than once and by pushing the long white plug at the back of the dash the light will behave correctly but the light and buzzer will come on again. I'm pretty sure the engined oil pressure is OK and that it's something electrical and it also looks like someone's been hacking at the wiring befire I bought the van. Has anybody got any ideas?

[ghost123uk]

Hi, in technical posts please state what engine you have, Petrol or Diesel etc

Sounds like he has perhaps either fitted the wrong sensor to the high pressure tapping or got the wiring wrong.
One of the few places you can rely on to get the CORRECT part is http://www.brickwerks.co.uk/shop?page=s ... gory_id=45" onclick="window.open(this.href);return false;

One of the oil pressure sensors is open circuit when engine off and the other is closed (and opens when the engine is started, iirc that is the low pressure one, but I might have that the wrong way round !)

Also worth a read = https://club8090.co.uk/wiki/Al ... and_causes" onclick="window.open(this.href);return false;

Oh and Hi and welcome by the way

[ghost123uk]

Cropped from that wiki entry by the way =

Mike says: If the high pressure switch (near the water pump, assuming petrol engine) wiring is open circuit, or the switch the wrong one or faulty, or if the oil pressure is low (of course!!!) you will get the light and buzzer when the revs go above about 2000. If you earth the wiring and the buzzer still goes, check for break in circuit somewhere (14 pin plug under dash cowl one suspect.)


To identify your wires:- When you switch the ignition on, (Engine not running) the oil light should flash. (No buzzer should sound)

Disconnect the wires one at a time and the one that puts the light out is the one which should be attached to the low pressure switch (between the push rod tubes left cylinder bank.)

Grounding (Earthing) the other wire will stop the buzzer as a temporary measure (if you are sure of your oil pressure of course !!!) That assumes the wiring to the buzzer circuit is sound, any break in the wiring and the buzzer will sound even with the wire end grounded.

So, try earthing the wire that goes to the sensor under the water pump (assuming flat 4 petrol) and see if the problem goes away. If it does = wrong or faulty sensor (that one is very fiddly to get at !)