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Discussion Starter · #1 ·
Thought I'd start a new thread on my problems as things are getting odd!

2000 225, no mods that I'm aware of! Unknown service history. Roughly 100k.

Oil light had come on intermittently, I've since replaced the gunked up oil pick up pipe and fully serviced the engine.

This didn't solve anything as upon restart after a short while the oil pressure light came back on.

I've now just replaced the oil pump (genuine one), the one I took out (topran) didn't seem too bad though.

Again all seemed ok on start up but when gently revved the light came on, drop back to idle and it went off.

I've got an aftermarket oil pressure gauge fitted (came fitted in the car) and the readings are as follows

At idle on start up from cold, the gauge read 95 (psi I assume)

When warm (water temp at 90)

at idle it read 42
At 2000rpm it was 76
At 3000rpm it was 84

5 mins later and the fans have kicked in

At idle 34
At 1500rpm it was reading 50

Another 5 mins warmer and idle was down to 30.

Idle seems to be no prob but the pressure light comes on at about 2000 regardless of reving in one hit or slowly building the revs. But the light will go off at idle or if the car is restarted until the engine is revved again.

Are the pressure readings correct? Is the gauge (a real cheaply) to be relied on?

Hoggy mentioned on my other thread that it could be a sticking pressure relief valve, do the readings above point to this or discount it?

I've also taken a couple of videos of the engine running at idle, the light was not on, the actual sound is a lot less intense that this, my phone seems to have enhanced it somewhat making it way way louder than it actually is.

Tap the pic to see the video.





And last but not least, is this the pressure warning light sensor? The black plug that is coming out of the side of the oil filter housing? I ask because there's some not very clever looking wiring coming out of it, a single black wire that seems to have been repaired in at least 3 places!



Any advice gratefully received!
 

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2001 Amulet Red 225 coupe.Owned from new as well as a Nurburg VXR & an XR3, all from new.
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Hi, If that pressure gauge is correct the pressure readings are high, so that rules out the pressure relief v/v.
Its possible the wire for pressure sensor is shorting to earth, but engine does sound noisy.
I assume you have replaced oil filter when you dropped the sump & replaced the oil..
Hoggy. :D
 

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this might sound an odd question,please exuse me I've had a few beers,eight in fact,but you have the correct viscosity oil and the right amount on don't you ?
 

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Discussion Starter · #4 ·
Being such a cheap and nasty pressure gauge I'm not convinced that the readings are that accurate but they do indicate that there's pressure and the pressure increases with engine speed.

It's odd that if the readings are a bit high that the low pressure warning is sounding :?

If the black plug bit is the sensor that would trigger the alarm I'm inclined to replace the wire as its got at least 3 crimp connectors holding it together :eek:

It's had a new genuine oil filter and I'm using 10w40 vw oil. Levels are all present and correct!

Thanks for you input guys!
 

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2001 Amulet Red 225 coupe.Owned from new as well as a Nurburg VXR & an XR3, all from new.
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Hi JMH, Where have you got the oil pressure gauge tapped into ?
May be better if you connect it in place of the oil pressure sensor.
Replace the cable & the pressure sensor would be my next job.
Hoggy. :D
 

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You should probably have proved the pressure before you went ahead and changed the pump. You can get a cheap test gauge from Ebay and would have saved you time and money. At the very least you should have replaced the pressure switch as that's cheaper than an oil pump.

Next thing I would do is take Hoggys advice and look at the pressure switch.

Sent from my HTC Desire HD A9191 using Tapatalk 2
 

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Discussion Starter · #7 ·
yup probably should have, but i'd convinced myself it was the pump!

At least i know its definately pumping oil as both pump, pipe (and sump for that matter) are all spotless :lol: The pick up was pretty gunked up.

Been out and taken a look, the pressure gauge sender is tapped into the top of the filter housing (using the plugged hole) and the switch looks a tad crusty to say the least.

I unplugged the switch and ran the car and got the same oil light symptoms (i knew it would come on, but it did in exactly the same fashion).

I'm off to try and source a new sensor and replace the wiring and I'll report back!
 

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2001 Amulet Red 225 coupe.Owned from new as well as a Nurburg VXR & an XR3, all from new.
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Hi JMH, Excellent, was a strange set of indications, but happy to hear it's sorted, happy TTing. :p
Low oil pressure indication has to be taken seriously.
Hoggy. :D
 

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Discussion Starter · #10 ·
Thanks again for your help, I'm not worried about having spent the tim end cash on the pump, it's an investment in my eyes, it might have been just the switch all along, but the oil pick up was covered in crap so it might just have saved me a bigger problem.

Sadly its still not happy TTing yet, I've got a rattly noise to deal with and boost that's intermittent from ok to pin you back into your seat :?
 

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Have ou changed the pressure switch.. or a least cleaned it out... because it is teed with the pressure gage sender as well as your ECU pressure gage it may just bea issue there.. if you remove the gage sensor and theadaptor and put he pressure switch back in ou may not get a engine light... (theory being the pressure is reduced through the tee peice..
 

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tony_rigby_uk said:
Have ou changed the pressure switch.. or a least cleaned it out... because it is teed with the pressure gage sender as well as your ECU pressure gage it may just bea issue there.. if you remove the gage sensor and theadaptor and put he pressure switch back in ou may not get a engine light... (theory being the pressure is reduced through the tee peice..
Tony, he fixed it with a pressure switch and some replacement wiring :wink:
 
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