VE L76 & L77 Low Oil Pressure - P0521-00 DTC

[krusing]

This might be of some interest for the cause of a Low Oil Pressure issue,
and causing to trigger a DTC of P0521-00 to activate the MIL.

Vehicle in question -
2009 VE CalaisV, L76 AFM 174,xxx k/m, [some of you may know it was the one I was selling for a family friend]

This VE Calais with L76 AFM was causing a P0521-00 DTC to trigger, it almost activated every third/second time it was driven,
And we had troubles getting a RWC for it
It was VERY strange fault, but I had a challenge to sort it out,
And I did !!!

Any criticism is welcome.

What I did first,
I Ran a Live ECU test on the 2009 CalaisV Oil Pressure [on the said Car], it was running at 176 > 190 kpa Oil Pressure,

I then ran a live test on my 2012 VE CalaisV, L77 AFM and it displayed 300 > 340 kpa,

The OP Switch on the 2009 CalaisV had been changed by the Dealer 13 months/11,000 k/s ago,
And the DTC P0521-00 started becoming more persistent, especially coming up to its next service,
[This was the Third OP Switch installed, as the Dealer couldn't find the fault]

Being my OP Switch is a known/working unit operating correctly, I removed it from my 2012 CalaisV,
and place it in the 2009 CalaisV, and I had the exactly same Oil Pressure 176 > 190 kpa,

Thinking the oil has sludged up, hmm, maybe
So I drained the oil,
Removed the filter,
And its seemed a bit dirty as it sill had 4,000 k/s life left,
I then thought it has to have a blockage for a low OP DTC,

As I had removed the OP Switch,
and then removed AFM Wire Gauze/filter and noticed the wire gauze/filter has some thick crap on it,
Being I had already cleaned it not long ago, as this DTC was annoying me at the time,
I cleaned it accordingly,
I grabbed a small length of fuel hose (400mm), place it on the end of the Compressed Air Trigger,
Shoved the other end down the OP Switch Neck, and gave it a GOOD blast, it did blow back for a few seconds, and then cleared the vertical OP Switch tube/housing,
and then you could hear it bubbling, and then it cleared,
I got under the car and noticed more oil was dripping out,
So I let that completely drain,
I then re-fitted the -
AFM Wire Gauze,
OP Switch
New Oil Filter,
Sump Plug,
I then filled it with oil,
Started it up,
And then ran a live test on it again,
And the OP was back up to 300 > 320 kpa
So hopefully that has stopped the P0521-00 from Triggering,

So with what I possibly did,
I cleared the sludge on the OP tube, and possibly the sludge on the pickup,
Now we can get a RWC for the 2009 CalaisV.

Hopefully others will find this handy.

regards

krusing