My 1998 Dodge Durango, 5.2L engine, 120k, sometimes stalls at idle AFTER the rpm goes to 625 from 626 rpm (oil pressure at 25 psi). Then, at 625rpm, oil pressure INDICATION suddenly drops off-scale, the “check gages” comes on, the chime sounds, and engine can continue to run for a few seconds (the hydraulic valve lifters DON’T get nosier). Then, IF I don’t blip the throttle, the engine will shut down. If I see the “check gages”, and hear the chime, I can always blip the throttle, oil pressure will go to 25+psi, and the engine will run normally (with 25+ psi oil pressure), until I release the throttle. Then the engine might idle at 626 rpm, or, it might fall to 625 rpm, and the cycle starts again. The idle speed is not adjustable. It’s completely under computer control. Idle speed cannot be nudged to, say, 650 rpm. The computer will only allow it to go 1,000+ rpm, when one tries to nudge the throttle. = Yes, the engine oil is fresh, and the oil pressure sensor/sender has been changed. There are no DTC check engine light codes. The oil pressure sensor does feed the engine computer. The Haynes manual, the Chilton’s web site(via the public library), nor alldata.com (again, through the public library) offer a clue. What, in the electronics, is causing this precipitous oil pressure INDICATION drop, and stalling this engine? If I knew what, I could, hopefully, fix it, or bs the computer.
clean the throttle body and idle air by-pass port. That often will be all that is needed.