oil light flashing on/off
 

Hello all !
grand caravan LE 97,3.8L, AWD
For 4 days now oil light on dash turning on and off intermittently. Turns on as soon as I start engine. When I drive it turns off a few seconds then turns on again. my mechanic changed the oil pressure switch. did not fix problem. he changed the oil and cleaned the oil chambers to remove guck with penzoil cleaner then put in new 5w30. I had a small oil leak but even with oil topped up the oil light still lit on/off. my mechanic changed a gasket to fix the leak. Any ideas please the ding ding sound is driving me nuts !! thanks !!

Since you have already done the basics with this, I would look into changing the oil pump. How many miles are on the van? I think the pump is harder to replace so it might be costly. Although maybe your can drop the pan and inspect for sludge build up. This is very easy to do and can help to make a decision with it. If there is a lot of build up, then the engine might have damage but if it is clean on the inside it would be worth it to change the pump.

thanks for your reply andyg. the van has 150 000 km. the penzoil treatment was used to flush sludge and the mechanic applied air too with some oil to rinse it further. is this adequate for the sludge you mention ? I do not know the parts involved but is the oil pump the only other piece that is replacable in this system ?
thanks !

I don't recommend engine flushes. I prefer to pull the oil pan and clean it up myself so I can inspect the possible damage. The main parts of the oiling system are the oil pump, filter, passageways and bearings. At this point I would pull the pan, and inspect the bearings on the crankshaft and connecting rods. Maybe the bearings are worn causing lower pressure.

Does the light go off when the engine is above idle? If so does it stay off always when raised above idle? If so, I would think it is the bearings being worn. Although when engine problems like this, I would recommend that you do not drive the van. You risk siezing the engine if the oil pressure is low.

Andyg thanks again.
ABout the light: two different scenarios about the light.
the past two days it was colder and raining . when I would start the van the light and ding would turn on. After I would start driving it would turn off for a few km then on again. It even turned off for a good 20 mins at one point.now today it is warmer and dry and this morning the light was on and dinging non-stop. this is the same symptom as when this first started on last fri,sat, sun. i will pass your suggestions to my mechanic ,hope he can handle it ! have good day. Jessica

Have him drop the pan, I'll bet all the gunk/sludge has settle on the screen and clogged up the sending unit. Although it's possible the bearings could be warn, my bet is he'll find sludge in the pan. The pan, screen and sending unit can all be cleaned by hand and put back in. This will probably fix the problem.

Hi, I have a 2008 Grand Caravan. I have a similar problem with my oil light flshing and dinging. The van has close to 150,000 to 160,000 km's on the motor. The light ONLY dings and flashes when it is hot and comes to a stop. this doesnt happen all the time either but most times and after close to 20 minutes of driving. I have increased the oil viscosity to a 10 w 30 oil as the 5 w 20 seemed too light. This did stop the light for a while but it has come back. Now when I put the van in neutral at a stop light the ding and oil light will stop flashing for a bit, but if the car has been run for more than 20 or 30 minutes then this does not stop the dinging and flashing.

I am thinking it is the oil pump. How hard is it to change this out? Can a backyard mechanic do this?

If it were me I would change the sender, a cheap and easy option. If that doesn't do it I would connect a pressure gauge and get a reading on what the actual pressure is. If it's out of specs then go for the pump.