What Causes Low or Drop in Oil Pressure: Dodge Ram Trucks

A below average oil pressure reading or a sudden decrease in oil pressure can be signs of serious mechanical problems, and often triggers a check gauges message or low oil pressure light. For instance, a message from the instrument cluster might read “oil pressure low,” followed by a “shut off engine” warning. Use the following guide to determine what causes a low oil pressure reading or sudden drop in oil pressure.

Low Oil Pressure

When the instrument cluster triggers a check gauges indictor lamp or low oil pressure light, it’s a good sign that the engine’s oiling system needs servicing. Use the following guide to determine what would cause a low oil pressure gauge reading or low oil pressure light.

Drop In Oil Pressure

An abrupt, but temporary drop in oil pressure can have many causes. This condition often triggers a warning message on the instrument cluster that might read something like “oil pressure low” or “shut off engine.”

Upon getting this warning message, the vehicle might stall or idle rough for a few seconds. After a few seconds have passed, the warning message usually goes away and the vehicle starts idling normally. This problem often happens when the vehicle comes to a complete stop. 

Typically, the low oil pressure or shut off engine message has noting to do with a bad oil pump or bearing clearances. The most likely cause is when the charging system output is too low as a result of erratic idling. Therefor, fixing the idling problem will often remedy the sudden drop in oil pressure. Use the following guide to determine what causes an engine to stall or idle rough.

For vehicles experiencing a sudden but temporary drop in oil pressure, followed by rough idle or a stalling condition, it’s highly recommended to inspect the throttle plate for carbon build-up, first. Especially for vehicles that experience this condition when coming to a stop.

When there is excessive carbon build-up on the throttle plate or surrounding parts it will prevent it from returning fast enough to maintain proper air to fuel ratio. As a result, the engine will either stall or the RPM will drop suddenly and cause the charging system output to drop too low. When this happens the instrument panel will trigger multiple warnings, such as "oil pressure low” or “shut off engine. Some vehicles will also trigger an audible warning tone.

References

Clark Kay, et al. “2001 Chevy Trailblazer Low Oil Pressure When Stopping?” Automotive Questions & Answers, 28 Nov. 2020, www.cowsunite.org/question/2001-chevy-trailblazer-low-oil-pressure-when-stopping/.

“Oil Pressure.” Wikipedia, Wikimedia Foundation, 12 Nov. 2018, en.wikipedia.org/wiki/Oil_pressure.