1991 S2 Oil pressure problem
 

Hi everyone,

Driving cool on the highway, the oil pressure suddenly dropped to the red area, and a curious noise coming from the top of the engine happened.

We stopped the car and towed it to our house. After many investigations on the Internet, I spotted the OPRV to be guilty. I removed it today and tested it (without dismantling it) : the piston goes smooth and free within its sleeve. Could it be faulty despite its good looking appearance or should I investgate somewhere else ? After I put back the OPRV, the oil pressure level was about 2 at cold engine startup, with the noise still being here (you can clearly hear it in the video).

Many thanks for any help :-)

You need to provide some more detailed information.

How long have you had your car? How long has it had this issue? What maintenance, if any, was performed on the car prior to these episodes? What brand/viscosity motor oil are you using? What is the oil level on the dip stick? When is the last time the oil/filter were changed?

Hi !

I own the car since 2013, the issue began last summer and the car has not been used since then (it is parked in a family house where nobody goes when it's cold). No important maintenance has been done for some years (the timing belt was supposed to be changed in December but the rendez-vous has been delayed...). I do not think it is linked to the problem, but the alternator was changed a year ago, and the DME relay replaced in July. The oil is standard 10W40, the level is always fine (I check it from time to time, no consumption) and the filter was changed in December 2014.

I do not use the car a lot (about 6000 km per year) and it is now 210.000 kms.

Hope this help, thanks for your concern.

Edit : The topic has been published twice (my mistake), and in the other thread, there is a video file where you can hear the noise coming from the top of the engine (https://rennlist.com/forums/944-and-...e-problem.html)

Where you do live? From the way you write, you could be in Europe.

What is the ambient temperature range of your local climate? 10W-40 is not viscous enough for these motors. If the temperature is usually above -10*C, drain that 10W-40 and replace it with 20W-50.


https://cimg7.ibsrv.net/gimg/rennlis...62f11b4875.jpg

You've got an issue that needs investigating by a 944 pro. Although a heavier weight oil is well advised, changing to it will not solve your low OP nor your noise problem. I'm not able to open your video on my Mac, but would be interested in hearing it. There's not much in the top end that would cause OP to be low, but I'd still pull the valve cover and have a look for anything awry. Unusually low OP accompanied by a noise is typically caused by an oiled journal where clearance has become excessive causing both a large oil leak and a noise. Check the top end, and if you're convinced all is well there, consider a rod bearing issue. Again, these comments are made without hearing the noise, so I hope it's something simple.