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I have a problem with my oil pressure. When hot and accelerating strongly the oil pressure drops to ZERO or slightly above for a second or two and then fluctuates. Also, there is LOTS of valve noise. If I then put it in neutral and coast the oil pressure sits at around 2 and rises to 3 when revved, just like one would expect. When cold and accelerating strongly the oil pressure stays between 2 and 3. Seems like the hot, thin oil makes the oil pump much less effective? Last year I installed a new oil pressure sending unit with no change in symptoms. Before I drop the oil pan and replace the oil pump, are there any other possible solutions? THANKS!
Yeah, some valve noise seems to be constant. People always ask if it's a diesel, kinda pisses me off (lol). It does get noticeably worse when the engine is hot and climbing hills. Makes me pull over and freak out while I check the oil level and let it cool down before turning around! The temp gauge also climbs a little during that time. Definitely something wrong with the oil pressure, and not just a bad gauge or sender unit.
I had figured it was simply dirty valve lifters and, recently pulled the head to have it rebuilt while I disassembled and cleaned the lifters. Now have a new head gasket, all new rubber hoses, vacuum lines checked, cleaned EGR tube, etc. only to find that it sounds EXACTLY the same! Great compression and strong acceleration, no complaints there. Took the valve cover off last week to check for collapsed lifters and they all held strong. WTF! Maybe the low oil pressure causes a few of them to slightly collapse when the oil is hot? Read somewhere that there is an oil pressure relief valve that might be stuck open? Thanks for your time.
Been trying to get the oil pan off the vehicle for several weeks now. Purchased an engine hoist and have the motor lifted to the max (touching fire wall) but still can't remove the pan. Seems like the oil pump pick up tube might be in the way? Hard to tell what is stopping the pan. HELP.
Okay, got the pan off, just had to hoist the engine MUCH higher than I expected. WHAT A SHOCK to find the oil pump housing had disintegrated! The only piece left is about half of what's missing, so the rest must have been eaten by the pump gears. You can see the large hole in the screen too. Check out the attached photos.
As per the symptoms, we've been running the car with this pump since we bought it in 1998. Gee, my wife used to always say it got quite when the oil was at max level. And all these years none of the mechanics, dealerships, etc. ever noticed. They said that it sounded "normal" to them.
Yeah, makes me sick now to think about it every evening as I try to sleep. I remember losing the flywheel key when I rebuilt the head last year. Figured I'd find it one day cleaning up the garage. Well, it had fallen into the sump and must have gotten sucked through the screen. Then, as it got trapped between the pump gear and the housing the housing wall shattered. This is all supposition, but it makes sense. I had no idea other than losing oil pressure going up hills.
Everyone online kept saying it was a bad oil pressure gauge, so I eventually replaced that with no result. I'm sure that there is significant damage, just don't know if it's still really driveable until I have the new pump in and listen. I'm sure that I heard a bottom end noise just before I took the pan off. PISSER! Oh well, nothing to do now but install the new pump and run her. These engines can be had for fairly cheap and, if I had to, might consider buying a parts car. PISSER!
The major components that were possibly damaged are the crankshaft, connecting rods due to scoring or bearing failure. The cams and their journals might also be (scored) damaged..
I'll tell you brother... It were my car; I'd replace the oil pump and filter, button it back up and take her out for a 30-mile test drive listening to the engine. After 30-miles the oil is warmed up (thinned out). No bottom-end knock or cam-chatter.. You're good to go for another 5 or 50,000 miles. YMMV
Thanks Slick. I ordered the only new oil pump that I could find from Slovakia. Should be here sometime in Feb/March. Thanks for the encouragement and I will let you know how things go.
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