Car Care: Keep your car’s heart pumping
Search Driven for vehicles for sale
A flashing oil light could be the sign of a serious problem
We recently covered the importance of drivers keeping an eye on the oil warning light. It was in reference to a situation where, because of a lack of regular changes, the engine oil can eventually turn to sludge and start to block the oil pump strainer, among other things.
The engine oil pump is much like the human heart: it must provide a consistent and controlled flow of pressure so all vital components remain healthy.
In the case of a vehicle engine, if the pressure drops below a prescribed amount — because of a blocked oil pump pickup strainer — the warning light will either fluctuate on/off or stay on permanently after the initial engine start-up to warn drivers of a problem.
According to one of our trusted industry sources, some owners have become confused as to what the warning light means. One owner recently thought it referred to the oil level only. They checked the engine oil level after driving with a flickering warning light and found it to be sitting just under the full mark. A top-up of oil did nothing to stop the warning light flickering, so they assumed the problem was a faulty warning switch. The end result was a major engine failure.
On initial disassembly of the engine, it was found the oil pump strainer was almost totally blocked and the sump was full of sludge. Further investigation found the rest of the engine had suffered from lack of decent oil pressure over a reasonably long period.
The warning light will definitely come on when driving or take longer to go out after initial start-up if the levels are critically low (because of starvation of oil to the pump), but it’s not the only reason for the driver to take immediate action.
The engine oil pressure is set by the respective manufacturers to operate within a certain range. There are internal controls in place to ensure pressures don’t get too high and warnings to tell drivers when they are too low.
When warnings appear by way of the dashboard light it means the engine is operating below the “safe” pressure level and damage will occur if those warnings are ignored.
In the case of a blocked oil pump strainer, those critical pressures will start to run at undesirable levels, even when the warning light is not coming on and warning the driver of a problem.
There is a point when the oil pressure is sufficient enough to just keep the warning light out but borderline in terms of providing adequate protection to all vital parts of the engine.
Hence the need to take immediate action, especially if the light does start to fluctuate and levels are found to be all right.
So it’s not a bad idea to take a quick note of how long it takes for the oil warning light to go out after start-up, and to also listen for any harsh-sounding knocks from the engine while waiting for the warning light to go out.
When I heard about this particular failure, I automatically assumed the car was fairly old and tired.
But the truth was, the vehicle had not long come out of new car warranty and the engine oil or filter had never been changed from day one. So let’s reinforce the need for regular servicing, using good quality oil and oil filters.
And keep a close eye on those warning lights.