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Since this happened after an oil change and the oil level itself is OK, it may have been that the wrong weight of oil was added. If the oil added was too thin of a weight than the oil pump will have a hard time pumping it properly resulting in low oil pressure, especially at idle. You may want to ask the shop (or whoever did the change) what type of oil they used.
Wednesday, August 4th, 2010 AT 11:31 PM