It sounds like your reservoir sensor is sticking. I have not had this problem but there may be some posts on this forum or definitely at the yahoo previa group about this. Basically, it is reading as low and dumping oil into the engine. The easy fix is to pull the connector to the reservoir pump. You can also clean up the sensor itself but I am not too sure as I have never done it before. On the other hand, you may have a massive oil leak.

The supercharger oil is independent of the engine oil and you should check it/fill it as well. That oil can be filled with Castrol. I forget which weight (maybe 5w-50). Again, search here or at yahoo. The check/change that oil, I found the easiest way was exactly how the factory manual says to do it as opposed from the top.

Good luck.

 

It sounds like your reservoir sensor is sticking. I have not had this problem but there may be some posts on this forum or definitely at the yahoo previa group about this. Basically, it is reading as low and dumping oil into the engine. The easy fix is to pull the connector to the reservoir pump. You can also clean up the sensor itself but I am not too sure as I have never done it before. On the other hand, you may have a massive oil leak.

Good luck.

In my case, I believe the oil overfill was caused by the plug to the sensor coming unplugged. Previous owner's mechanic jury rigged a connector that kind of well, sucks. I disconnected the oil reservoir pump while I replace that plug.

At least I think that's what caused it. My oil pressure light isn't working either so I have other things to diagnose.

 

I am having the same problem, but I also have a massave oil leak that I havn't had the time to track down yet... it is sooo bad that the oil is blowing on my rear bumper and hatch... I go through a quart every 500 miles or so... I am starting to think that there is a leak in the line from the pump as my oil pressure light has never even blinked. To reset the oil level light, I have to pull the efi fuse ( same as resetting the check engine light). It doesn't go out on its own.

Oh, and the S/C does not have a sensor

 

So helpful!

midnightrunner: Thank you for the referral to the Yahoo group. I am finding tons of information about this oil sensor issue. Your advice is very much appreciated! I have a lot more to work with now....

 

I should clarify my post, the sensor is on the oil pan of the engine. When the oil level gets low, the reservoir pump gets activated. Well, that's my understanding of it anyway.

Yeah, between toyotanation and yahoo, all our previa repair needs are met (unfortunately).

 

The oil level switch is a float that rides on a shaft that makes contact at the top and bottom of the shaft. If the float is sticking at the low level it is going to turn on the pump and overfill your crankcase. You can unbolt the float sensor and remove it out of the oil pan and make sure the float rides freely on the shaft. I had to clean the shaft of my daughters van and now the oil pump and light are working normal. (I used some steel wool and sandpaper to clean the shaft) The best time to do this is when you change your oil so you do not have to dump good oil out whil you remove the switch.

 

I have a 1996 Previa at 127,000 miles that has recurring issues with the oil reservoir draining.

About every 4,000 miles, the "oil level" light comes on. I check the level in the engine and it reads full. Then I check the reservoir and it is empty. So I add 2 quarts and I'm good to go for another 4000 miles/couple months. I've never found another Previa owner who experiences this--most say that those same 2 quarts have been sitting in the reservoir forever.

I talked to a mechanic about how frequently I have to replace the reservoir oil and he told me this is normal for cars with my mileage.

Now there is a new problem:

• 1,000 miles ago: the oil level light came on, so I put 2 quarts in the reservoir, filling it to the top; the light went off after 30 miles or so
• 700 miles ago: I got an oil change
• 200 miles ago: the oil level light came on; I discovered the reservoir was completely drained already; I put 2 quarts of oil in the reservoir
• now: the engine level reads full, the reservoir is full, but the oil level light is still on

What the heck is going on here? One Previa friend of mine added oil to her supercharger once--could this be where the oil is lacking? Could the light be faulty?

I have to drive to Colorado (several hundred miles) this weekend--I'm not sure if it's safe to drive or not, even though by my account the oil levels are in fact normal. Anyone have any ideas??

Thank you thank you!

My 97 Alltrac has a problem with the reserve pump running at start-up. It seems to over fill the engine just a little then stops after a few seconds. i just had the engine rebuilt and the idiot POS so called mechanic that claimed to know how to reassemble everything screwed it all up. Any information on how the reserve oil is supposed to work would be greatly appreciated.

 

Where did you have it rebuilt?