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Discussion Starter #1
I changed my front brake pads myself yesterday (pretty impressive for me!).

Car was fine before I did it, and I started the engine a couple of times whilst jacked up so that I could turn the calipers towards me using the power steering. However, when finished, on starting the car I got the engine oil pressure low warning, and each time subsequently. Car runs fine though.

I check the oil level weekly as advised and it is currently exactly on the max mark, so lack of oil can't be the problem. I don't appear to have a leak either. Any ideas?
 

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Coincidence? :confused:
 

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Sounds like the oil pressure sensor has gone. Just coincidence it's coincided with you pad change.
 

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Bloody dodgy Italian cars. :rolleyes:
 

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It's this everything electronic jazz, don't you reckon? Can only get worse as cars get older or is that too pessimistic of me? Could check it out with a coupled engine oil pressure tester,bit expensive though, about £30 or so.At least you would then know whether you had to hunt for electrical faults or not.Good Hunting.
 

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Please correct me if I'm wrong but I think the oil pressure sensor is a switch. When there's no pressure it earths the lead to the dashboard and when there is pressure the connection to earth is broken.
I'd suggest getting a multimeter set to Ohms (2000) and measuring the resistance between the the sensor and earth with the engine off (should be 0 Ohms) & then when it's running (should be high impedance) .
If it is always 0 Ohms I would replace the sensor ASAP and if the new sensor is also always 0 Ohms it's time to start panicking.
I agree it's 10x more likely to be an electrical or sensor fault but oil pressure is not something to gamble with.

Also if you have no pressure the tappets shoud get rather noisy.
 

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Sounds good Bodger. Sender units, old terminology, now become sensors, is that correct? On 147, whats the readout message, light, or have some pressure gauges? Correct me if I'm skewed, oil pump feeds mains, big-ends, squirts bores, small ends, then up to valve gear, drains back to sump? Think you would hear major noises with pressure failure. Thats why I suggested any potentially expensive doubts, physical coupling of gauge. Then after sigh of relief, out with multimeter, electronic test gear.
 

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How old is the car, and how many miles has it done?
 

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Chris, that is certainly not a dumb question! Brake job, wear indictor connections, float level in master? Thats the problem with 'On Air' diags. Can't see the physical problem mate, need to see what's what.
 

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Discussion Starter #13
Car is 2002 with 53k miles. I just wondered if it could anything to do with starting and stopping the engine after only about 10 seconds 2 or 3 times. The message is displayed on start up and simply will not disappear, but the engine runs and sounds fine.
I'm on the verge of swapping the thing for a spider so the timing couldn't be worse!
 

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Have you had it from new...are there any knocking noises?
 

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This picture shows the location of the pressure sensor.
My guess is that the wire to it is disconnected or that the terminal is corroded and needs cleaning.
 

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Discussion Starter #17
Fantastic, I'll give it a go.

Thanks for all your help, off to the garage if I can't fix it, fingers crossed though
 

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Had same problem 2 weeks ago...

I've got similar mileage on mine... Low oil pressure, replaced switch at dealer and hey presto. All clear.
 

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Interesting, plenty of problems in this area yonks ago.Some of the senders/ sensors, actually leaked oil where the pressure closure of the steel body, failed to seal around the plastic body of the switch/sendor/sensor/ not necessarily with the warning light illuminating, just the oil coming out! Remember some of the models Wrenched and Co?Way before electronic this and that!
 

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I don't know if you saw but the sender trips at 0.2 bar of pressure.

I think that equates to about 2 PSI meaning that a low oil pressure indication will always be either wrong or too late.

I bought 2 Boxer cars with shot big ends and both owners reported that the oil light hadn't come on!

A pressure gauge is a good investment IMHO.
 
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