Based on the symptoms, I'd suggest having the pressure checked with a mechanical gauge. If you don't have a dash gauge, you probably don't have an oil change reminder light either. Those are only found in a few car models. Extended mileage between oil changes won't make the warning light come on either.
Engine mechanical problems will usually result in lower oil pressure at idle. Speeding up the engine increases the output volume and pressure of a worn oil pump. Low pressure due to worn bearings will also show up at idle. The fact that the warning light comes on at 1200 rpm suggests a problem with the spring-loaded diaphragm in the sending unit. That's why the pressure should be checked first with a mechanical gauge, so you'll know exactly what you have.
Caradiodoc
Sunday, January 17th, 2010 AT 11:48 PM