schlag

I'm still trying to track down the low oil pressure problem often associated with these cars. This is I think my third post in the past year on this topic, and each time I accumulate more and more data. I'm definitely not the only one having this problem.

What I am looking for are people who've actually solved this problem, and details into actually how they fixed it.

The problem is normally a "sticky" start, ie. when starting the vehicle after sitting for a day or more, it takes up to a minute or more for oil pressure to come up past the bottom/zero level. Until then, the engine taps like mad.

In my case (in particular), once the car warms up a bit it will "flicker" into the 0/low pressure zone when at idle or very low RPMs.

One thing I've noticed more recently is that when it flickers into the low/0 oil pressure zone, the idle dips very slightly.. its almost an oscillating idle, but unsteady.

I took the advice in one of the previous threads and re-sealed the front of the oil pump, replaced the sleeve and actually resealed the entire front of the engine but it still has these problems.

So has anyone with these symptoms really solved this yet?? Does this sound like the oil-pressure relief valve, or something more dire?

Thanks!

adrial

Is it safe to assume that you're using a Mahle oil filter?

schlag

But of course

Waterguy

Porsche has several TSBs out on the OPRV. It seems that when they brought out the one piece OPRV in 1987, the early build cars got one that was not treated to inhibit corrosion. It is recommended that these valves be replaced with the later corrosion-resistant OPRVs when doing oil cooler seals, etc. If you provide your engine (not car) serial number, I will check to see if you have an early one-piece OPRV. If so, corrosion of the valve may be your problem.

Super Dave

I am having a mech. shove a camera up in the oil pan and providing it does not have a baffle I will know if the pick up tube is off or not. My car has the three piece (stress a piece) OPVR. IF the tube looks correct. He is going to throw a used OPVR on it then check the oil pump drive for tightness. I really do not have the time to mess with this car right now thus the mech. But I will post my findings once known. I took some time last weekend, but to no avail, Thanks Kevin Baker for your help last week.

Waterguy

There is a one-piece OPRV that is the replacement part for the older 3-piece valves. Expensive, I believe. Part number is at home.

ahofam123

I am just finishing the fight with my low oil pressure issue. On a cold start, my car took 30 seconds to build oil pressure. After replacing the pickup tube seal, the rod bearings, and wetsanding my 3 piece oprv, the car now takes 2 seconds to build oil pressure. With the new rod bearings, my warm idle oil pressure also jumped from about 1 to about 2.5.

Super Dave

I so much do not look forward to droping that susp. and oil pan on this car to replace that pick up seal.

kinda5150

ok, this is a shot in the dark but it worked for me: i simply used engine flush twice and that solved my problem. did it once, but still had the pecking. then immediately drained the oil and reflushed it a second time. after refilling it took just a minute or so to stop pecking and it's been all good since. i'm sure everyone will eek at this suggestion, but it worked for me. hope this helps.

Baron009

My car idled somewhat oddly when I started it up after it sat for a few days. It would be around 900-1000, then drop considerably - seemed like it was going to stall, and then made its way back up to around 1000rpm. Does that sound normal?

Kevin Baker

Schlag, mine's done 100%. I just replaced the little o-ring that goes at the end of the oprv. Check in the 1999 technical reference manual, bulliten #3 it will have the part #'s for the o-ring, and the crush washer that you need. My oprv turned out to be OK, the o-ring had just disintegrated. Part # 944-107-935-01 should be the o-ring for the post 87 cars.

Super Dave

Kinda5150
"after refilling it took just a minute or so to stop pecking and it's been all good since."

Do you really mean 60 seconds or so?
Thats what I am saying is BAD. It should not take more than 2 to 5 seconds to stop ticking if at all. Mine ususally shuts up at around 1.25 to 1.75 minutes. Uh, thats 1.25 to 1.75 of excrutiating unlubricated grinding.

Kevin Baker

Shouldn't take that long, when I crank it, it catches, the revs go up and the light goes out, after that it sits at idle.

ahofam123

I would definitely check the oprv before tearing the suspension apart. The only reason that I dropped the oil pan was because I finally gave up on it and took it to the mechanic to diagnose (he said that it had a cracked oil pickup tube).

Super Dave

FIXED!!!! uh, guess what? it was the oprv. replacing the 3 piece valve with the shorter of the two new style valve did it. My mech robbed one off of a 87 924S motor and let me have it for $90.
It now jumps up to 2.5 bar immediatly with no gas. then shoot right up to 4.75 when the gas is pushed.
Ya hoo!!!