Hi All,
Customer called in on his way home on Friday evening, in a panic, with no power.
Fault codes P0089 SCV stuck, P1272 Pressure limiter malfunction and P1275 Supply pump exchange.
Cleared codes and P0089 returns (it's the only one that does).
Agreed to have look on Saturday, never really works that, does it?.
Removed SCV and the plunger did feel odd when pushed so I took it apart, cleaned it and inspected it. It was suffering quite badly from scuff marks on the side of the plunger. Lubricated and refitted it with no change.I felt it was possible that the valve was letting by due to the scuffs.
Unfortunately the customer was unable to resist temptation and had to keep coming in to see how I was getting on! He ordered a new SCV (from P.F.Jones) and I fitted it. No improvement.
The vehicle has a Ralliart boost kit on it (standard fit on the Animal I believe) which I temporarily disconnected. No change.
Live data shows actual rail pressure at 76MPa and target at 50MPa at idle (when the code is set). Unfortunately the system faults out before I can get the data up on the screen to see what it is without the code set.
I think a rail pressure sensor is possible but that is a complete rail to replace. What I don't have is a high pressure test kit to check the sensor against a reference value. The other possibilities as I see them are faulty drive signal to the SCV caused by a wiring or ECU issue. I intend to scope the SCV signal to try and check this. If it is a drive problem it would be typical for it not to give an SCV open circuit fault code I suppose .
Any suggestions?
Shaun