Low Oil Press. - Toyota Nation Forum : Toyota Car and Truck Forums

cmtwok · 02-26-2010, 08:06 AM

Hi, I just bought a 91 Toyota Corolla and the oil light will come on when I come to a stop or slow down, then go out after I accelerate, unless I just started it for the day, when it is still cold. A friend of mine had a Corolla yrs ago ago and it did the same thing. He flushed it out w/ something and it fixed it. Any suggestions or past experiences would be greatly appreciated.
~jim

***zythr*** · 02-26-2010, 09:44 AM

Hi: Have you checked your oil level to see if it is not low? Maybe the flush idea that your friend used could work. Hopefully you don't have a weak/failing oil pump. Good luck

eage8 · 02-26-2010, 11:55 AM

I would change the oil first and see if that helps. also look in the oil for any metal shavings or anything from the oil pump.

cmtwok · 02-26-2010, 12:02 PM

Thanks for the replies. I did change the oil and its where it suppose to be. When I did change it, there was quite a bit of "sludge" that came out. And it did seem to activate the oil light at lower RPM's.
~jim

90 GP · 02-26-2010, 03:32 PM

Might try replacing the sending unit for oil pressure light. Your sender might be on the way out.

blb · 02-26-2010, 03:49 PM

Quote:

Originally Posted by 90 GP

Might try replacing the sending unit for oil pressure light. Your sender might be on the way out.

I agree with changing the oil pressure sending unit. That will usually take care of the problem.

cmtwok · 02-26-2010, 04:07 PM

Oil sending unit? Isn't that the sensor to turn on the light, the gauge? Thanks again for your replies. This site is awesome!
~jim

90 GP · 02-26-2010, 06:55 PM

The sending unit is the threaded sensor with the wire plugged into it on the side of the block .
Here is a picture of one from NAPA.

http://www.napaautoparts.com/Search/...+50070+2070008

ktownkrolla · 02-26-2010, 11:39 PM

Quote:

Originally Posted by 90 GP

The sending unit is the threaded sensor with the wire plugged into it on the side of the block .
Here is a picture of one from NAPA.

http://www.napaautoparts.com/Search/...+50070+2070008

Right on man...all i use in my shop is NAPA parts.

toyotaspeed90 · 03-02-2010, 05:26 PM

it's a single wire sensor located on the exhaust side (has a yellow wire with black stripe, IIRC) near the oil filter itself.

if the light is coming on then you have very low pressure, possible for concern.

when doing a flush don't use anything other than AT dex3 (or similar) fluid -- all of the flushes that are sold are very highly corrosive and if you leave it in too long it can cause havoc elsewhere. Put in 1 quart of dex3 and let it run (either at idle or drive around the block, but not mashing on the gas) for about 10 minutes, drain it when warm.

When I do this method I usually dump about 1/2 quart of new oil through to help pick anything extra up from the pan. I would recoomend just for trial use 10w40 or thicker.

the specifications only call for about 6psi on idle (which is very low pressure) so if the light is coming on, there might be cause for concern.

cmtwok · 03-07-2010, 09:16 AM

Thanks for the replies and ideas. I changed the oil and did not affect the oil light from coming on. Changed the oil pressure sending unit and that did the trick.
Thanks again...
~jim

90 GP · 03-07-2010, 11:42 AM

Glad to hear you got it fixed.