My oil pressure sometimes bounces a bit between 4 and 6 bar. This doesn't happen consistently, but when it does it is typically under WOT at around 7k RPM. It's a DEFI setup with the sensor mounted in a line off the motor.

Pressure never falls below 4 bars and it typically only blips for less than a second or so. Any ideas? I've never worried about it, but had someone in the car with me today that commented "... wtf is up with your oil pressure!?" So I thought I'd post here.

TIA,
-MSM

 

Who knows what a "bar" means to Defi. The oil pressure should vary from 75-100+ psi above 4k.

 

1 bar = 14.5037738 PSI There are hopefully a few here familiar with the metric system.

Question is whether there is anything to be concerned about in the pressure quickly bouncing btwn 4 and 6 bar at 6 to 7k RPM. In other words, pressure is constant at about 6 bar then for a brief moment it bounces down to 4 bar and back up to 6. Throttle is WOT all the way through.

 

Your 1st post says "bars", similar to the stock coolant temp gauge reading "3 bars".

I've never seen my oil pressure gauge fluctuate at WOT, it's always pegged on 100psi.

The SPA technique gauges I've installed fluctuate some, as they have a digital readout. Not much more than 10-15psi fluctuation.

 

So you're seeing about 1/2 the fluctuation I am. Where is your SPA technique sender mounted?

 

The SPA gauge sender is mounted directly off a 10AN feed hose from a Canton Oil filter relocator.

My Autometer sender is located on a Greddy Oil filter block.

 

My Defi sender is mounted off a 10AN line also connected to a canton oil filter relocator. Are you running an Accusump? I am, with the 24 PSI release valve. I've confirmed that the valve is releasing at 24 PSI (2 bar ). I get the pressure fluctuation described in my previous post with or without the accusump turned on.

Do you think the 20 to 24 PSI fluctuation is something to be concerned about? Any ideas on potential cause?

 

No acuusump, but the car does have a massive oil cooler in a custom C&R radiator, as well as a remote Canton filter.

It's my understanding the accusump's valve opens at the preset psi, which is well below your operating pressure.

I'd want to verify the gauge accuracy 1st, to make sure the Defi gauge is telling the truth.

Can assume you've verified proper oil level, after you have filled the accusump? The possible causes for the fluctuation that I can think of are:

Flakey gauge
Oil pump picking up air (low oil level)
sticking pressure relief valve

 

wtf ap2 has oil pressure gauge???? where have i been living?

 

He has a DEFI gauge installed on his car. No S2000 come with a guage, only a low pressure idiot light.