no just on start up and has done so before after washing. I was looking on the 540 E39 forums and it's documented there. Seems to be a clogged filter or bad switch located by the oil filter. I'm thinking of just replacing that. I have had the pressure checked and it's fine as is oil level. I think the cam position sensor is gone as well so it is doing two things here. The CPS has thrown codes before but my mechanic forgot to write down which one and cleared the code!!! Was waiting for it to happen for the last three months so we could see which it was. Looks fairly easy as a DIY so I may change them myself if I have time this week. Need a good DIY document for a 4.4i though. Most are for 3.0 that I can see.

Thanks