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Low oil pressure and engine clicking sound

edited November -1 in Repair and Maintenance
95 Nissan Quest, 145k

It started with the oil light on and off. It was on when stop or slowing down and the light went off when accelerating over 25 or 30 mph. I did find there is an oil leaking somewhere. I planned to take it to garage for check up and the symptom disappeared. I used the car for short trip about two weeks and the symptom did not come back. I checked oil almost every day since then.

Recently when I took a trip on highway, the light came on after about 30 miles. I stopped and checked oil. The oil was all right. I started the car and light did not come on at the beginning. However, it came on (blinking) after 5 minutes of drive and I heard a clicking sound. I had it towed to a lcoal garage.

The mechanic found a severe leak and need to replace ?gasket? or something like that, about a couple hours of work. He said the noise properly was from the lifter. However, when he checked the oil pressure, the pressure continued to drop to about 8 lb. He said the bearing properly worn and I will need a new engine.

It properly not worth to replace the engine since it is 15-year old. But before I say good-bye to the car I just want to get a second opinion. Could it be something clog the oil pump screen? Would it be good to check that first? Is there anything I can do (within a reasonable cost) before declaring the death of the car? Thank you for your advices.

Comments

  • edited March 2011
    If you have low oil pressure it could be a tired oil pump OR increased bearing clearance in the bottom end of the engine. You could try to replace the pump with a high volume pump or in the meantime use a thicker oil. I would put 20W-50 in your crankcase unless you live in Alaska...its too cold there for that weight of oil. The thicker oil will be able to fill in the extra clearance opened up in the bottom bearing and increase your oil pressure.
  • edited March 2011
    Your description seems as though you developed an oil leak, ran dangerously low on oil, and are now experiencing low oil pressure issues. If you didn't have excess bearing clearance before, you do now. Start saving for a replacement vehicle now. In the meantime, you can keep driving this one, but do not let it get low on oil again. As suggested, heavier weight oil may help increase oil pressure if it's a bearing clearance issue. The way it is now, though, the engine may last another week or another ten years. It's impossible to tell, depends on how lucky you are, and how vigilant you will be with the oil level, which is why I say start saving now.
  • edited March 2011
    I have gotten some suggestions on how to take care of my car problem and I would like to get some input on these suggestions and decide which way I shall go.

    One suggestion is to remove the oil pan and check if there is any blockage on the oil pump screen that could cause low oil pressure, and also check the oil pump and the bearing?s condition.

    However, I was told it is probably a waste of time and money (a couple hundred dollars) for the above action. So here is another one which suggested an engine flush with Amsoil or Seafoam to remove any deposits if any, and then replace it with synthetic oil after the engine was cleaned. My concern is that since the car has a leak somewhere, would the engine flush cause more serious leaking problems?
    In regard to the oil leak, I know people have been using a stop leak product for worn out seal problem. Just wondering if that will work for my case.

    One approach is based on if the low oil pressure is basically a worn bearing problem (since the mechanic put a gauge in to directly measure the low oil pressure it is less likely to be a oil pump or blockage related issue), I could just try to change the oil with thicker oil to see if the oil pressure increases and then forego the oil pan and/or engine flush approaches.

    I hope to get some input on these and I really appreciate your time and advice.
  • edited March 2011
    Winter anywhere in the northern half or so of the U.S. is to cold for 20-50 would be my guess
  • edited March 2011
    "Could it be something clog the oil pump screen? Would it be good to check that first? Is there anything I can do (within a reasonable cost) before declaring the death of the car? Thank you for your advices."

    I would drop the pan and check the screen before I drove it to the shredder..I have seen oil-pump intake screens so plugged up they would float in a can of solvent..
  • edited March 2011
    Eight pounds of oil pressure sucks and the mechanic is probably correct.

    Before doing anything with the vehicle I'd drop the pan. The pan and pickup screen can be inspected for sludging or coking when the pan is off.
    While the pan is off a few of the bearing caps that are located the fartherest away from the oil pump should be removed and the bearings inspected.

    If the bearing overlay is washed away then it's time for another engine if you choose to keep the vehicle. (preferably a used engine considering the age of the car)

    From the sound of things the engine may be in sad shape based on the comment about having to travel 25 MPH or faster to turn the light off. Don't go out of town with the vehicle at this point.
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