Oil pressure light on with oil pressure?

[porschetub]

Hi ,have driven car with 2.7 inserted ,feels very strong but I believe my oil pressure is too high (4.5+bar @ 4000 4.2 bar @ idle ) and the oil pressure light runs on with good oil pressure but not always.
The light is dim or fully lit ,should I do the following;

1 - Drive on like a fool and not worry remembering it was oil pressure or lack of it that killed my 2.5
2 - Change oil sender unit.
3 - Inspect oil pressure relief valve
4 - Check oil pressure light
5 - Give up for today and
Cheers Dean.

[Cocacolakidd]

What are you measuring the oil Pressure with? Possibly a faulty sender?

First check the wiring to the OPS (Oil Pressure Sender) clean and make sure it has the best contact.

I would check Sender and or replace it - they are not that expensive, and are easy to change out - Then if the same problems are still occurring check the OPRV as it may need service or replacement - easy enough to get to and clean/service then replace the o'rings and top crush seal, a little spendy to replace, but if necessary a must do.

Also check also the wiring to the gauge panel as it may have a loose connection or there could be a corroded connection there.

By the way - that is normal Oil Pressure for cold/cool motor...

[Cocacolakidd]

Also see: Clark's Garage Home Page
Garage Shop Manual - section 03 Oil Pressure

Allot of good information there at Clark's

[porschetub]

Thanks,changed out the sender and checked connections all ok,no change ,the pressures I gave were for cold oil but it does'nt drop much when up to temp anyway.
This engine showed oil pressure warm of 2.5 @ idle and 3.5 -4.0 bar @ 3 - 4000rpm when in the other (later) car, my 85 is the old type instrument cluster.
I believe my 2.7 will have the upgraded OPV, I didn't know they could wear out like the old ''piston'' type ones ?
Would replacing damaged/ worn ''o''rings be a recondition for this part?
Do you know where the oil light gets its signal from ? or does that come from the gauge sender also?
Will check OPV next.
Thanks for your time.

[kdjones2000]

I had my light start to flicker on while driving down the highway. No change at all in the analog pressure, but the light started flickering and eventually went to full on.

My problem ended up being a faulty sender; once I replaced that, everything worked as it should.

On the late cars at least, there are two wires coming off of the oil pressure sender. One controls the analog gauge, while the other one controls the oil pressure light.

Make sure that you have the correct part for the oil pressure sender (If there is any difference, not sure).

[krystar]

and those numbers are good on oil pressure.

2.5bar hot idle is fine. the light is not supposed to come on unless u have less than 0.5bars. u prob have a faulty sender or a faulty light. maybe it's a short or something on the bulb wiring.

[porschetub]

Thanks all for the fast replies,I don't know if I could be unlucky and have 2 sendors faulty but you never know.
Clarks mention the gauge should read max (5 bar) when the ignition is on,mine isn't doing that - it comes up from the rest position to 0 bar (ignition on) and then goes up very quickly on start up, could this indicate the wires are transposed?.
Will try changing over sendor wires then check the dash light connections,cheers

[HondaDustR]

I found with the wires reversed on mine, the guage will read 0 with the ignition on and instantly peg when the motor builds pressure, but it would also never move from the peg as long as there was oil pressure, probably because the low oil pressure switch stays open as long as there's pressure and the guage pegs on an open circuit.

[wild man]

Might be that the wire feeding the light is shorting to ground somewhere. Try disconnecting it at the sensor terminal and see if it still comes on.

[HondaDustR]

Which "end" does the voltage feed from? From the sender to the dash or from the dash through the sensor.

[wild man]

The wire for the idiot light is the negative lead from the bulb itself, of which the other lead is connected to 12 volts when the ignition is on. As long as pressure is above the point at which the switch makes contact, the light will not illuminate. If pressure drops below that threshold, contact is made from the wire to ground, providing the current path which will light the bulb.