I fear the worst (bearings) because this car has overheated a couple of times, but I have seen this light come on before.

The key is that it runs pretty good when cold and for short trips in city. Once I drive 45mph or more for any length of time over 5 minutes, I get the oil pressure warning light at idle, and the car is sluggish.

I changed to a much thinner oil recently and suspect that as the problem--it happened once before after an oil change. I am first going to flush it and then refill. I may take off the pan but haven't ordered a gasket and want to test my theory first.

Thoughts?

 

LR recommends 0W40 synthetic for the Freelander V6. There is a routine check for oil pressure that involves removing the sensor and attaching a manual gauge. This is done to determine if the sensor is faulty, or if there is actually low oil pressure. The sensor is cheap, located adjacent to the front crank pulley, and relatively easy to replace.

If pressure is indeed low, it is probably the oil pump. The crank will survive low pressure at idle, but the cams will not as they are on the tail end of the system. The front bearings can seize and break the front pulley off.

 

Thanks for that,Rick. I increased viscosity and that helped--light doesn't show up now at idle. The key seems to be that the car has to run for about 15 min. or at 50mph for shorter periods. I get some odd misfiring action and lose power. A whining sound is heard, too. My buddy put a code-reader on it after a drive and it showed p 1471 and p1475--which suggests intake wiring or bad VIS motors.

It's possible that the heat causes a short and the poorer running keeps rpms too low. But the oil pressure seems to be connected to this. Car runs fine until it gets good and warm...

Puzzle!

 

Actually, I did replace the sending unit (it was loose sitting in there!), but that didn't solve it. Could it be the oil cooler is clogged? That would make the oil run a little hotter, right?

I also wonder if the pan has sludge or the pick-up is clogged. I did do an oil flush before I went to the thicker oil...

 

Yes, the oil cooler can clog, but only if the pick up has been pulling sludge from the pan. If the engine has been lubed with traditional, non-synthetic oil, it will form a significant amount of sludge that can fill the pan up. It is hard to drain the sludge out through the drain plug, so it is best to remove the pan from the engine and clean it, it is a relatively easy task, and only requires an anaerobic sealant to replace as there is no gasket. Note that you must remove the lower engine torque mount at the rear of the pan, along with the dip stick and mount for the oil cooler.

Once off you can clean the pan out, and clean the pick up as well. Replace the o ring on the pick up where it enters the crank girdle so there is no loss of suction.

If there is I a heavy build up, it can cause the oil pressure problems noted as the low speed flow is greatly restricted. The sludge is formed because the engine runs very hot in comparison to other makes, and traditional oil will separate. It will also accumulate in the lifters as well.

The VIS motor codes will not turn the check engine light on as they do not affect emission problems. They will cause a loss of torque as they are designed to vary the length of the intake runners to match engine speed. Check the second plug in from the engine side on the ECU for corrosion as to the misfire.

 

Hey, Rick.. Changed out the intake manifold because one of the venturi valves was sticking. STP solved (for now) the check engine light.

Now I will have to see whether I have sludge, a bad pump, or whether or not I probably have bearing wear.

Cheers,

Bill

 

Bill, I have a hunch it is a combination of sludge around the pickup which is restricting the flow, and viscosity. The oil pan doesn't use a gasket, and comes off easily enough. You re-seal with an anaerobic sealer although some people use silicone. Good luck!