Oil pressure indication - a problem?

[The Red Baron]

I've noticed that if I press the loud pedal hard in 5th gear and revs passing through 4000 the oil pressure needle drops smoothly towards zero in synch with the throttle pedal movement. If I take my foot off the pedal and allow the revs to drop, the oil pressure needle returns to normal (30 - 35 psi). I haven't noticed if it does the same in other gears.

Normal oil pressure indications when warm are: at idle = 20 psi, at cruise (5th gear @ 2800 rpm) about 30 - 35 psi.

I use Mobil 1 and alway keep it topped up.

Is this apparent drop in oil pressure normal? I don't get any other warning lights and I've not kept my foot down very long with the indication so low. I thought perhaps it was an indication of the oil pump cavitating??!! Any other ideas?

Thanks in advance for the advice!!

[Bluebottle]

4k rpm in 5th gear does it do it at 4k rpms at a less scary speed like say...2nd gear?

[The Red Baron]

The speed may be less scary in a lower gear, but the acceleration is definitely more scary!!

I haven't had the balls to look while in a lower gear.

Will have a look shortly.

BTW I'm not in the UK at the moment - I'm somewhere with a more relaxed view to speed limits!! That's when I noticed this issue.

[Bluebottle]

lol..I didn't necessarily mean for you the be accellerating, just holding at steady speed at 4k rpm's

[spend]

See what happens when do 4krpm in neutral... sounds like it will be fine and it may just be the wiring needs some TLC at the engine end.

[dumbfunk]

Yup - I've had to change the pressure sender twice due to silly wiring problems.
Being stuck on the bottom of the sump I think it can get a pretty rough time from speedhumps and road debris no matter how careful you are.

[Barreti]

My oil pressure sender is on the Offside of the engine not down at the sump.
Did they move them for later cars then?

Red Baron you have bigger balls than me doing 4k rpm in 5th. Nice one

My car feels like a wright brothers plane at anything over a ton, what with the wing mirrors flapping, bonnet rattling and a tornado inside the cockpit whipping anything in there up and around.
Thats OK on track but on a road its a tad scary and terrifies unwary passengers

Edited by Barreti on Tuesday 30th March 10:59

[spend]

Yes Ian they are in a different location.

[Barreti]

Cheers Dave. Still livin' an learnin'

[spend]

Barreti said:

Cheers Dave. Still livin' an learnin'

More like still showing your ignorance

...but who cares about all that new fangled overweight rubbish anyway

[yellowgriff]

Sound like a sticking oil pressure release valve problem..Had this on a audi once many years ago..

[marks3drtaz]

I Had the excact same prob on my other griff a few years ago, the sender is under the engine and as you accelerate the engine tilts and the plug is pulled ever so slightly from the sender as the wire is fixed to the chassis. At worst you may have worn engine mounts.

Mark

[The Red Baron]

Thanks for the interesting diagnosis. Glad its not some sort of lack of oil pressure to the engine. It does it in all gears and only when accelerating hard.

I've got it booked in at TVR Power for a few mods, so will get them to look at it then.

Just come back from a 200 mile blat, top off - just brilliant.