QuestionQUESTION: I changed my oil in my 2000 Chrysler Sebring to a high mileage, 5w blend. Since doing so, I am having problems with the oil pressure. What could be causing this?
ANSWER: Hi Bryan,
If your previous oil has been 10w or higher then the oil warning light is coming on (probably at idle, correct?) because with a "thinner" oil the pressure at a given rpm is naturally going to be lower than previously. So as long as this light goes off as soon as you raise the rpm above idle I would not be concerned about it. The warning light comes on at a higher pressure than is actually required at idle rpm (6 psi). If you want to return to the status quo before, then, next time switch back to 10W oil at the next oil change. An oil pressure gauge can be inserted in place of the oil pressure warning light sensor to verify that you have at least 6 psi at idle if you want to check that out as it stands with the 5W oil.
Roland
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QUESTION: Update: I was driving and the oil light came on it started running rough and it just died. ( when I was at low rpm) It was recommended I change oil pressure switch/sending switch so I did. It's still coming on and starts running rough (again low rpm)I didn't go very far before it started happening so now I am afraid to drive it. Could it be the oil pump? It is an ji convertible with 127,000 miles. Not close enough to take and get a diagnostics done to it. Thanks for your help.
ANSWER: Hi Bryan,
The oil pressure warning light may well cone "on" because the engine rpm was at idle or even less than normal idle due to any number of possibilities that cause rough running. The only concern about the oil light would be if it came 'on' and stayed 'on' while the rpm was staying over 1,200 rpm. So unless that is what happened, rather than it came 'on' only when the engine was stumbling, I would not focus on the oil pump or the light being 'on'. Rather, focus on why the engine was running rough.
To do that use the ignition key: turn it "on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then watch the odometer window to see the mileage reading be replaced by a four-digit number preceded by a P or replaced by the word "done". Tell me what you saw in the window and we'll go from there. The engine controlled has a self-diagnostic capability and this is how to get a fault code number which is diagnostic of the problem you are having.
Roland
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QUESTION: The oil light stayed on and mileage window just shows miles still. How far do I turn key? To first or 2nd? Tried both. Should the oil light be on still? Thank you for helping.
AnswerBy "on" I mean the key position where it is when the engine is running (not the 2nd position which operates the starter). Don't start the engine! Do it in less than 5 seconds total time.
Then see if anything shows up in the mileage (odometer) window.
At what rpm reading does the oil pressure light go off, once you have the engine started?
