Deano_P1

When changing my oil today i noticed that when i turn my ignition on the oil light doest show. Checked and found that the little sensor behind the alternator wasnt plugged in!!

Since plugging it in it now comes on when the ignition is on, and when i start up the engine it seems to go off but when looking closely you can see that its very dimm

Could this just be a faulty sensor?

s70rjw

iTrader: (2)

Is your filter on tight enough and is the oil level correct?

Deano_P1

Yes all seems fine

jasonius

iTrader: (1)

What age scoob is it..?

I noticed this recently on my 05 WRX, although it only occurred with ign on engine not running. Posted a similar question about it actually..!

Does the oil pressure effect the brightness of the light I wonder..?

Turbotits

iTrader: (2)

Two possible reasons for this, One is the oil pressure is low. Do you have a guage? The other is the switch is knackered. Its been disconnected i would assume to hide either one of these problems.


If its dim all time. i.e. at idle and at higher revs then i would think its the switch

Deano_P1

Its MY00
I am waiting for my guages to arrive at the moment.

Yes its dim all the time..bright when the ignition is on but when you start the car up it goes dimm and stays dimm both at idle and when driving

jasonius

iTrader: (1)

Ah, this was the exact opposite of what mine occasionally does..

Deano_P1

Anyone else seen this before?

Im thinking if it was to do with the oil pressure the engine would have gone by now as ive had the car 6weeks....hope its just a faulty switch

mike2.5subaru

Turbotits (nicename ) is right it's the switch. It should light the light until a predetermined oil pressure is reached, this fault is not unheared of on any car, it is an on/off type of switch, like the ignition light, above the predetermined pressure the light should be off below and it should be on

Deano_P1

When the car is first started it is bright but after a split second it goes dimm.

Its annoying in the dark because u can clearly see it but in the day you struggle to notice it

Turbotits

iTrader: (2)

Yea change the switch. There not to expensive and easy to change

Deano_P1

Im currently waiting for some guages, including an oil pressure guage, to arrive.
Will the oil pressure sender replace the existing pressure switch?

Turbotits

iTrader: (2)

Its unlikely that the oil pressure sender for the gauge will delete the o/e switch. normally they either use the bung above no 3 cylinder or a sandwich plate at the oil filter. The o/e switch is under the alternator where you connected the wire to.

I suggest you keep the o/e switch and light as well as a gauge anyway.

Deano_P1

Cheers turbotits!

One thing i noticed today is that even though its dimmed its slightly brighter at idle but when ur driving or if u rev the engine it becomes harder to see (gets dimmer)

Deano_P1

Has anyone experienced this problem with their oil light before? Did it get dimmer as the revs increased?

Deano_P1

Can anyone think of a reason why the oil light gets dimmer when i rev the engine??

hades

I can think of a reason in that the oil pressure will increase when engine revs do. Can't quote specifics on your car, but my previous car's oil pressure would drop to maybe under 1.5 bar if it got really hot and then left to tick over at 600rpm, 2 bar at normal tickover, rising to perhaps 3-3.5 bar come 1000rpm and 5 bar at 1500rpm, which is as high as it got. However, as has been said before, depending on how the circuit is set up, the light should be quite close to a digital on/off. As you've got a guage coming anyway, I'd say fit it a.s.a.p. and keep an eye on oil pressure. If the pressure is low, find out why. If it isn't, change the switch.

Deano_P1

If the oil pressure was low at the moment surely the big ends would have gone by now tho?

Iv had the car for nearly 7 weeks and done over 1000miles and it runs fine with no unusual knocking etc

hades

If it was really low, yes something would have broken, and at that stage you'd expect the light to be on brightly. If it's just slightly low, you'll quite probably have no obvious adverse effects, possibly issues if pressure drops more (e.g. the engine left to tick over whilst really hot) or suffering from slightly accelerated wear.

This is all fairly hypothetical - my money would be on a sensor problem. However, my engineering brain always likes proof that the important systems are doing what they should when something like this throws doubt in their direction.

rigga

iTrader: (4)

Bad earth...... classic impreza's suffer from this.


Though other symptoms such as poor starting might also be apparent...... try a new switch first.

scubasteve

As he said

Sounds like a bad earth, I had this on a previous car

Deano_P1

What would poor starting show?

Although i wouldnt say its poor starting up....but it doesnt start up instantly like my old clio sport did