low oil pressure 1.5-2 bar on gauge

TheStig · 11-20-2001, 12:48 PM

I have a problem that maybe something serious. Today I was running the car through the windy backroads. When i came to a stop at the light after going through them, I stepped on the clutch and brought the car back to idle....BUT when it went back to idle the engine bogged and the oil light came on (it has done this for about 2 weeks now) and when it returned to idle the pressure was only at 1.5 bar. at the next idle it was between that and 2. Could this be an oil pick up problem???? anyone know what this is? I also am hearing a noisy lifter in the head too. The oil is fine in the car cuz i just changed it and added a quart about 6 days ago. Anyone have any ideas?????? the car has 135,000 miles on it now.

wolfrpi · 11-20-2001, 01:08 PM

yeah - your engine is getting old. Welcome to the club. 1.5 bar is fine. My oil light used to come on a lot. Try and put 20-50 in it and see how it runs then. That cleared up my problem 20,000 miles ago.

Magnus_944 · 11-20-2001, 11:44 PM

My pressure was also low, it could go down to 1.2 or so but the oil pressure ligth never came on. I was running 10W40. Now I use 10W60 and pressure stays up above 2 all the time, downside is that Castrol 10W60 RS is not cheap...

/Magnus

Bob's944 · Bob's944's Garage

try 15W40 diesel oil (like Rotella), it holds up for the big turbodiesels, lil 944 engine aint no sweat for it. Those other gas engine oils can't stand up to Rotella... all you need is 15W40 in that stuff ... not sure they even make a higher weight, but if it's needed in your area, I'm sure it'll be available. 15W40 is all that is available in Florida and that'll take on all the heat Florida can throw at it.

mike944 · 11-21-2001, 06:34 AM

Eurospec-
You might want to have that looked at since the problem came on suddenly. It could be something as simple as the oil pressure relief valve sticking. If it was just normal engine wear, it would have happened gradually over many years. My '84 has about 150K on it, and the oil pressure is around 3.5-4 bars at idle, even after the oil is hot. when it's cold, always 5+ and hot, over 2000 rpm, 5+ bars. I use mobil 1 15W-50 in the summer, and i really drive it hardly at all in the winter. Last winter, i think i had 10W-40 or 10W30 (dino juice) in it, this is the first year i have had synthetic in it.

Myself, I wouldn't use diesel oil. It's not intended for gasoline engines. But, as you see, a few people use it, and only time will tell if it causes problems. Read my reply to this post about diesel oils, http://www.pelicanparts.com/cgi-bin/vb/showthread.php?threadid=26165 I don't feel like retyping it here.

Mike

Bob's944 · Bob's944's Garage

Note.... diesel approved oils ARE APPROVED for all gas engines, it's just not the reverse. Gas engine oils would get destroyed in the high pressure diesel world (the one I own is 22:1 compression ratio) so the diesel oils are engineered better. It's just a better oil. PERIOD. I have found virtually no viscosity breakdown after 5,000 miles in my 944, gas engine oils were breaking down fast at 2,500 miles and becoming useless, no matter what brand. The opposite is true of diesel engineered oils, I've found no brand that breaks down significantly at 5,000 miles (I'm almost confident enuf to let it go anuther 5,000 miles w/o changing, I just think it's too long... i might change my mind in the future). So don't let the diesel approval fool you, it's just saying that you CAN use this in diesels also, but you can't use the crap made for gas engines. There is a whole list of manufacturers of hundred thousand dollar turbodiesels that know the real deal on oil. It's perfect for high performance gas engines, don't be prejudice, yeah... diesels turn slower, but they deal with far greater pressures and temps. Maybe you haven't seen a Rotella lable... here's one..

Bob's944 · Bob's944's Garage

ooops....here

Scott R · Scott R's Garage

Still back to the above post, your problem came on suddenly. Putting thicker oils in your motor is just a band-aid. Your just going to mask other problems. I had some of the same symptoms as yours on my 85.5. I turned out to be a worn oil pump gear that was skipping around and not driving the pump correctly. When I replaced the belts I did the pump gear as well and my pressure was still a bit low. So like the above post stated I cleaned and adjusted up the relief valve and it ran an 4+ from there forward. Low oil pressure is not something to be taken lightly. You can starve the lower mains and loose a rod easily. I have seen many dead 944 motors that were starved, and then threw a main, usually #2 first. My 85.5 had 129K on it and still held 3.5 to 4+ at idle and above the 5 marker under load.

TheStig · 08:22 AM

Scott where and how do you clean the pressure relief valve for the oil? I am thinking thats the same thing too since I have heard so much about it on the board. I just wanna know where it's at and is it hard to get to....do I need a mechanic to do it?

BTW: I use Mobil 1 15W50 since my car had turned 100,000 miles. It has stopped almost all oil leaking from my car and it has made the engine run alot smoother.

porsche1984944 · 11-21-2001, 07:20 PM

Does anyone use Valvoline Max Life?

Bolkboy7 · 11-22-2001, 02:06 PM

Does anyone read Auto Week? My neighbor lets me borrow his after he reads it thoroughly. It is a great magazine. Anyways the 911 TURBO uses three quarts in beak in mileage and after that it consumes about one quart every 500-1000 miles after that. I know that is not true to my 1984 944 but i just thought that was an interesting fact.

-Lee