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Low oil at idle 2001 Express 2500 5.7

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Old April 1st, 2019, 3:58 PM
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Default Low oil at idle 2001 Express 2500 5.7

Hello,
I have a very low mile van at 76,000. I picked it up last year, drove a 100 miles and it seemed to want to stall, but then it was fine except for the oil gauge dropping down just above the red zone at stop lights. I thought it was going to be the oil pressure switch, so I changed that and the oil/filter today. It now seems to be even a little worse with the check engine light coming on briefly at stops until I rev the engine up some. PLEASE HELP!!! Thanks
Old April 1st, 2019, 7:28 PM
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Oil Pressure Diagnosis and Testing

  1. With the vehicle on a level surface, allow adequate drain down time, 2-3 minutes, and measure for a low engine oil level.
  2. Add the recommended grade engine oil, and fill the crankcase until the oil level measures FULL on the oil level indicator.
  3. Operate the engine and verify low or no oil pressure on the vehicle oil pressure gage or the oil indicator light.
  4. Listen for a noisy valve train or a knocking noise.
  5. Inspect for the following:
    • Engine oil diluted by moisture or unburned fuel mixtures
    • Improper engine oil viscosity for the expected temperature
    • Incorrect or faulty oil pressure gage sensor
    • Incorrect or faulty oil pressure gage
    • Plugged oil filter
    • Malfunctioning oil filter bypass valve
  6. Remove the oil pressure gage sensor or another engine block oil gallery plug.
  7. Install an oil pressure gage.
  8. Start the engine and then allow the engine to reach normal operation temperature.
  9. Measure the engine oil pressure at the following RPM:
  10. Specification
    1. 42 kPa (6 psig) minimum, at 1,000 RPM
    2. 125 kPa (18 psig) minimum, at 2,000 RPM
    3. 166 kPa (24 psig) minimum, at 4,000 RPM
  11. If the engine oil pressure is below minimum specifications, inspect the engine for one or more of the following:
    • Oil pump worn or dirty
    • Malfunctioning oil pump pressure relief valve
    • Oil pump screen loose, plugged, or damaged
    • Excessive bearing clearance
    • Cracked, porous or restricted oil galleries
    • Engine block oil gallery plugs missing or incorrectly installed
    • Broken valve lifters
Old April 1st, 2019, 8:59 PM
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Take the sending unit out and spray some parts cleaner in it or replace it. Use an air hose and blow into the hole where it screwed into the block. Sending units are usually cheap so if it's easy to get to replace it anyway.
Old April 3rd, 2019, 8:32 PM
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Sounds like your RPM is dropping at idle.try looking into a tune up. If engine is wanting to stall then lights will start to flicker on the instrument cluster.
Old April 3rd, 2019, 8:44 PM
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My 2002 did the same thing. I bought it at 110000 kms, and when i stopped at a red light it would go down to the top of the red zone on the oil pressure gauge. Popping it into neutral would raise the rpm a bit and it would climb just above the red zone.

I switched to high mileage oil. (valvoline max life....) it made a noticeable difference. Under the same situation, the gauge no longer dropped to the red, and showed higher oil pressure at all ranges. Drove on high mileage oil from then on, and no problems whatsoever with the engine for the next 130000 kms.
Old May 2nd, 2019, 8:50 AM
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My 2002 2500 does this. I've put 2500 miles on it and no issues. Figure it's the sender or it has synthetic oil in it.




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