2003 carrera non turbo no oil pressure

Sorry, new to posting on forums and this may be a little long winded. Working on a 2003 carrera non-turbo for a friend. Car sat for a year and a half without being run. We got the car running and it smoked like a freight train. After running for a while and coming up to temperature the smoked cleared out. We took the car out for a test drive and all seemed well under "normal" driving. After driving for a bit we decided to put the car through its paces a bit and as the car went to shift to 3rd gear the oil pressure dropped to 0 and the warning came on on the dash. Shut the car off checked oil level everything was good restarted the car and still no oil pressure. Drove it 7 miles back to the shop with 0 oil pressure showing with no problems. Let it sit over night started it and oil pressure was back. Another test drive and same thing oil was fine driving easy as soon as it goes to shift to 3rd under full throttle oil pressure drops to 0 and warning light comes on. Tried same scenario 2 more times and every time it goes to shift to 3rd under WOT oil pressure goes away and won't come back for a couple of hours of sitting. I am at a loss anyone ever heard of something like this?

That does seem odd! First thoughts are bad oil pressure sending unit, or a loose or faulty connection. Pressure sending unit lives on top of the passenger side bank and has 2 spade connectors. I'd double check and see if those are tight, if they are then I may go ahead and replace the sending unit. Could be the gauge but after sitting for a while combined with the age of it, my money is on the sending unit. Either way not necessarily something you want to chance so you may want to see if there is a knowledgable shop nearby, or if you can hook up an analog oil pressure gauge to verify what you are seeing, as you don't want to keep running it if it is actually dropping pressure. At the end of the day I doubt the oil pressure is actually disappearing, rather false alarms from the electronics as these motor are not known to have oil pumps fail... Another thing you could do is pull the oil pan and check the oil pickup tube but if it was clogging up I doubt it would go straight to zero. Just typing out loud now Good luck, let us know how it goes, and welcome to the forums!

Thank you for the reply. I did check the connections last night at the sending unit and they seem clean and tight so i ordered a new sending unit. Keeping fingers crossed. I also check the pressure spring in the oil pump as i have seen where others have found them broken and it is in one piece as well. I will check the pick up tube and see if by chance it is plugging up. Just odd to me that is does at what seems to be exactly the same time every time, only under full throttle and as it shifts to 3rd. I was sort of wondering if this isn't a cam phaser issue. Like they are trying to adjust the cams and just creating a massive internal oil bypass It is showing an dtc for both cams being out of sync i believe it is p0012 and p0022

Thanks for the welcome and thanks for the reply Checked the sender connections and all seems fine there so i ordered a new sending unit unfortunately i will not have it for a couple days. Checked the oil pump pressure spring too as i have seen a few people have found them broken and it is still in one piece. Will drop the pan and check the pick up tube for any issues while i wait for the sender. just strange it seems to do it at the same point every time only under full throttle and as it shifts to 3rd. Starting to wonder if there is a cam phaser issue that is creating a massive internal leak at that point. Checked it with my scanner and it is showing both p0012 and p0022 cam sync codes

It’s the oil pressure sending unit It’s a common replacement part

Yep Easy DYI with extension, knuckle and crows foot Inexpensive too

Quotes source post: 10348784

You are welcome. Sounds like you may have separate issues, as I said I'm not aware of any 0 oil pressure issues with these but anything is possible. Regarding the cam sync codes, I haven't looked them up but makes me wonder if that is the reason the car was parked... Then makes me ask if you are familiar with the IMS bearing issues on these cars? Could very well be a failing IMS, or a number of other issues within the timing system, bad tensioners, tensioner pads, etc causing them to be out of sync. You may want to pull the valve covers to take a look at things before running it much more. Also I assume that you have done an oil change and checked the filter for IMS debris, correct?

Not the 51 modes of failure sky is falling IMSB. Oh my. Change the sender and post the codes.

Alright first off, Thank you to everyone that replied to this issue. The new sending unit came in yesterday and seems to have cured the issue. Took the car out for a nice long ride after install and oil pressure seems to stay within spec now even under wot. Smoke has completely cleared after driving and warming up a few times. The previous owner "says" the ims issue was already addressed on this car. I did find some magnetic particles in the lower oil cover when i had it off that bother me. Guess we'll see how this goes

[QUOTE=madscience;10352419]Alright first off, Thank you to everyone that replied to this issue. The new sending unit came in yesterday and seems to have cured the issue. Took the car out for a nice long ride after install and oil pressure seems to stay within spec now even under wot. Smoke has completely cleared after driving and warming up a few times. The previous owner "says" the ims issue was already addressed on this car. I did find some magnetic particles in the lower oil cover when i had it off that bother me. Guess we'll see how this goes[/QUOTE If you are referring to the oil "pan" sump plate that is not good. Hopefully you cleaned the plate of all debris. Often owners find debris like this from a failing IMSB & replace the IMSB with a new one before selling the car. You should get a oil sample sent of to LN engineering soon!

Congrats on solving the issue! I would definitely drop the oil filter and replace it. Inspect the one that is in there and see if there is any debris. as BYprodriver said, could be leftover from a previous failed bearing that was left over then replaced. Could also be an issue though, oil filter swap is quick easy and cheap to get an idea. If you find debris in the filter I would be concerned... maybe drive it a few more times then replace it again - if you still have debris, I think you have a problem. Not a bad idea to go ahead and take samples of the oil each time and send one to LN as recommended above~ Good luck!