no cel when low oil

[wally748]

hello i posted several weeks ago about oil seals on my 93 camry le i4 with 118k miles. it had been loosing about 1/2 qt. every 3500 mi. i suddenly lost 2 qts. in about 600mi. and had some seals replaced (oil, cam,&crankshaft)my question is no lights came on when i lost the 2 qts.i just happend to think about checking it. i disconnected the wire from the pressure switch &still no lights is the pressure switch bad or something else?when i turn the key to on all lights come on .all help appreciated. thanks
wally748

[Gibson99]

the oil pressure switch is just that - a pressure switch. it is not an oil level sender. if there's enough oil you will still have oil pressure. when there is no oil pressure the switch shorts to ground. you can test this by turning the key to the ON position with the engine off, and the oil light will come on. the check engine light should also come on, but this is unrelated to the oil pressure switch.

asking why the oil pressure light didn't come on for low oil is kinda like asking how come the front door of my house didn't automatically open when you pressed the doorbell. The two aren't directly connected, they just both have the word "oil" or "door" in their names.

[wally748]

Originally Posted by Gibson99

the oil pressure switch is just that - a pressure switch. it is not an oil level sender. if there's enough oil you will still have oil pressure. when there is no oil pressure the switch shorts to ground. you can test this by turning the key to the ON position with the engine off, and the oil light will come on. the check engine light should also come on, but this is unrelated to the oil pressure switch.

asking why the oil pressure light didn't come on for low oil is kinda like asking how come the front door of my house didn't automatically open when you pressed the doorbell. The two aren't directly connected, they just both have the word "oil" or "door" in their names.

0k i understand thank you

[Mike Gerber]

Exactly what Gibson99 explained. The only time the light will come on for low oil volume, is if the volume became so low that the oil pickup, mounted in the oil pan itself, could not reach any oil to pickup and pump thorought the engine. If that happens, the light will come on simply because there is not enough oil to pump and therefore 0 pressure is produced.

Mike

[wally748]

thank you

[Eye8Pussies]

from experience....you have to lose at LEAST 3qts out of the 4.5-5qts that the 3.0 1mz can hold (so, I think it'd be similar in ratio to the i4) before oil pressure (at operating temps) is low enough to trigger the oil pressure light

[wally748]

Originally Posted by Eye8Pussies

from experience....you have to lose at LEAST 3qts out of the 4.5-5qts that the 3.0 1mz can hold (so, I think it'd be similar in ratio to the i4) before oil pressure (at operating temps) is low enough to trigger the oil pressure light

[wally748]

thanks ,for some reason i always thought if i lost as much as 1 qt. my pressure would drop and kick the oil light on. now i understand how it works