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Q: Oil pressure fluctuating and clicking noise from engine.

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I have a 1995 Jeep Grand Cherokee with a 5.2L v8. About 80,000 miles. I recently had an alignment done, and now I am having trouble with my oil pressure. (Probably not related.) When the engine is idling, the oil pressure is about 2/3 of the way up, and as I speed up, the oil pressure gauge wiggles and twitches, and sometimes drops to about half way. When I drive fast, (60mph or faster), the gauge stays around the 2/3 mark.

What concerns me most is that there is sort of a clicking noise coming from the engine. It doesn't sound quite like a "no oil" piston slap or whatever, but still it doesn't sound good.

I had the oil changed after it started, and I've checked it several times, and the oil levels are good. Also, no check engine lights or anything, and the engine temp and voltage and idle and everything seem normal.

My car has 80000 miles.
My car has an automatic transmission.

Hi there. The noise seems to be a lifter tap. Either a lifter is stuck or there is no oil to the lifter causing the rocker arm to tap and creating the noise you are hearing. Try putting one quart of Ford Type - F automatic transmission fluid in the engine and running the engine for 15 minutes at 3,000 rpm’s. This will thin out the oil to help clean up the lifters. Then change the oil and the filter with new oil and a new filter. This should clear up the lifter tap. However, if the noise does not go away, then I recommend replacing all of the lifters and cleaning out the push rods. If you need further assistance with your lifters tapping, then seek out a professional, such as one from Your Mechanic, to help you.

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