LOST JEEPS
http://www.lostjeeps.com/forum/phpBB3/

Oil Pressure Light
http://www.lostjeeps.com/forum/phpBB3/viewtopic.php?f=5&t=62379
Page 1 of 1

Author:  Dave01 [ Thu Sep 01, 2011 1:44 pm ]
Post subject:  Oil Pressure Light

I got an oil pressure warning light the last few days when I dropped to idle. As soon as I'm over 1200 rpm it goes away, never see it unless I come to a stop. I just did an oil and filter change and it's still happening. I'm running Mobil 1 5W40 Turbo Diesel Truck Synthetic oil and Mobil 1 M1-301 filter. I know I'll have to get a pressure gauge on it to see how low it's dropping but does anyone know the pressure that triggers the light, or has anyone else had the problem?

Thanks,
David

Author:  turbobike [ Thu Sep 01, 2011 2:05 pm ]
Post subject:  Re: Oil Pressure Light

if you search the forums, you'll find that several folks have had this issue (me included).
I've replaced the oil pressure sensor and that helped for awhile, and used different brands of filters, and brands & weights of oil & the lite just comes on randomly...nothing I can definitely point to. truck is running fine--no strange noises. I've taken long trips with no issues. When it does occur, I do the obvious checks,,,looking for leaks and check the oil level, but nothing shows up.

good luck...I hope it's nothing serious.

Author:  jeepdan [ Thu Sep 01, 2011 3:11 pm ]
Post subject:  Re: Oil Pressure Light

A CDR owner near me has had the same problem. I think he said that he even replaced the sender and the problem never went away completely. His son installed a mechanical gauge and the pressure is fine, he lives with the idiot light coming on now and then. I will try to find out what the oil pressure is that he is seeing and get back to you.

Author:  Dave01 [ Thu Sep 01, 2011 3:41 pm ]
Post subject:  Re: Oil Pressure Light

jeepdan wrote:
A CDR owner near me has had the same problem. I think he said that he even replaced the sender and the problem never went away completely. His son installed a mechanical gauge and the pressure is fine, he lives with the idiot light coming on now and then. I will try to find out what the oil pressure is that he is seeing and get back to you.


That would be great if you can find out. My guess is the sender trips at 25 or so psi, and the pressure drops to 20 at idle, something along those lines. The problem is it's dangerous to guess about oil pressure problems! I also don't like listening to the "ding" every time I come to a stop.

Could you also ask him if he tee-ed the mechanical gauge into the same place as the sender permanently, or replaced the sender temporarily.

Author:  geordi [ Thu Sep 01, 2011 3:46 pm ]
Post subject:  Re: Oil Pressure Light

If your engine hasn't exploded, your oil pressure is fine.

Chrysler chose to locate the oil pressure sender at the WORST possible location for an early warning device - At the LAST place that will have oil in the event of a catastrophic loss of pressure or leak.

The sender is located across from the output of the filter, which is the second place oil goes after being picked up by the pump - So as long as there is enough oil left in the pan to fill the filter and the pump (about 1 qt should do it) then there will be enough pressure to keep that light off.

Unfortunately, this will do NOTHING to protect your engine from exiting this life rather violently. I lost a turbo shaft rather violently, and the result was that the oil pump pushed 4 quarts into the exhaust in about 30 seconds. The oil pressure light NEVER CAME ON. What I didn't know at the time, was that the #1 cylinder had just starved for oil, and was damaged severely. 10 miles later on the test drive after replacing the turbo and refilling the oil... The #1 cylinder abandoned its duty station quite messily. Again - The oil pressure light didn't come on, until the gaping hole in the pan had let ALL the oil out.

If you have that light... Replace the sender. Got the light again? Replace the sender again, they are chinese crap. That light WILL NOT HELP YOU detect an engine problem before you know about it from the violence happening under the hood.

I am working on a design for a completely new location on TOP of the motor that will actually HELP in monitoring the vital oil pressure... More to come on that soon.

BTW: I checked from the stock location with a mechanical gauge, and my oil pressure at idle was in the mid 60's for pressure way down there at the outlet of the pump.

Author:  cerich [ Thu Sep 01, 2011 4:19 pm ]
Post subject:  Re: Oil Pressure Light

had that happen a few years ago, changed the filter and oil and never came back. i would try that inexpensive route first....I am sure the filter was the problem

Author:  Dave01 [ Thu Sep 01, 2011 5:57 pm ]
Post subject:  Re: Oil Pressure Light

That's what I did today, changed oil and filter, no difference. I can't imagine that would be causing the problem, but then again the Mobil 1 M1-301 isn't a stock filter for these. It sounds like plenty of people are using them though.

Geordi, thanks for the info, very helpful. I'll put a new sensor in and see what happens.

Author:  CATCRD [ Thu Sep 01, 2011 7:09 pm ]
Post subject:  Re: Oil Pressure Light

Oil pressure on a cold engine is 60psi, but with hot oil it's about 18psi at idle and 30-40 cruising down the road. It climbs steadily with rpm. I use the M1-301 filter and Rotella 5W-40. I don't know what pressure the light comes on at, but usually those are pretty low, like single digits.

Author:  Dave01 [ Thu Sep 01, 2011 7:12 pm ]
Post subject:  Re: Oil Pressure Light

Ok, so in the first 20 miles after the oil change, no difference, the light came on at idle. After that, no more light. Very strange, I'm pretty sure it will come back based on the comments I've read here.

Author:  warp2diesel [ Thu Sep 01, 2011 9:10 pm ]
Post subject:  Re: Oil Pressure Light

That is why I have an oil pressure gauge, I don't trust Idiot lights.
When my GlowShift Oil Pressure gauge was acting up, I got a hold of them and their Tech Ran gave me the resistance values to determine if the error was the gauge or sending unit. Turned out to be the sending unit and they sent a new one under warranty.
If you don't want to cough up for an in cabin oil pressure gauge, buy a 100 PSI mechanical gauge from your hardware store along with a grease gun hose and the adapters to mount the gauge onto the hose. Unscrew the sending unit and screw in the grease gun hose gauge combo and start the engine. You should have about 20PSI at idle with a hot engine and more when cold. If the engine tests out, buy a new sending unit, they are cheap.

Author:  painemann [ Thu Sep 01, 2011 9:14 pm ]
Post subject:  Re: Oil Pressure Light

geordi wrote:
I am working on a design for a completely new location on TOP of the motor that will actually HELP in monitoring the vital oil pressure... More to come on that soon.

BTW: I checked from the stock location with a mechanical gauge, and my oil pressure at idle was in the mid 60's for pressure way down there at the outlet of the pump.


I would love to know where your thinking of putting tee for the oil pressure!
I would like to get oil press, boost, water and trans temp gauges asap!
I am so used to watching all the vitals on my powerstroke, I don't like not knowing whats going on when I get in the Jeep!!

Author:  geordi [ Fri Sep 02, 2011 12:27 am ]
Post subject:  Re: Oil Pressure Light

Actually my location changed recently, and I need to go on a spelunking expedition into my engine bay to see if what the book says is available... IS, and if it would work for a mounting point.

If so, then we have a potential spot that not only already exists with a plug in it... But would give equal measure of pressure feeding BOTH the turbo and the cylinders. It seems like the perfect location. I will see if I can do something about it tomorrow if it isn't too excessively hot here.

Author:  Drewd [ Sun Sep 04, 2011 7:26 pm ]
Post subject:  Re: Oil Pressure Light

Remove the oil pressure sender connector and spray it with some electrical contact cleaner. Make sure you shake it and let it dry then reinstall.....this worked on my wife's GC CRD which had the same problem except a chime came one with the low pressure light.

Author:  Patrick Henry [ Tue Sep 13, 2011 10:55 pm ]
Post subject:  Re: Oil Pressure Light

My '05 just started the low oil pressure light at idle routine. Cleaned the connecter, changed the filter and ordered a new pressure sender unit. :cry:

Author:  Dave01 [ Tue Sep 13, 2011 11:04 pm ]
Post subject:  Re: Oil Pressure Light

Dave01 wrote:
Ok, so in the first 20 miles after the oil change, no difference, the light came on at idle. After that, no more light. Very strange, I'm pretty sure it will come back based on the comments I've read here.

The light has stayed off. I don't know why the oil change made the difference, but so far it's cured the problem.

Author:  cerich [ Wed Sep 14, 2011 9:11 am ]
Post subject:  Re: Oil Pressure Light

the back pressure valve in the oil filter most likely failed...

Author:  Patrick Henry [ Sat Oct 01, 2011 12:41 am ]
Post subject:  Re: Oil Pressure Light

A new pressure sending unit solved my indication problem.

Page 1 of 1 All times are UTC - 5 hours [ DST ]
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
http://www.phpbb.com/