oil light turns on

[StocK-CB]

why would the oil light turn on, my autoshop teacher said it was cuz it had low pressure. But then it went away when i replaced the oil pan gasket and filled it with 20w-50. one day it truned on again after driving it hard in the city and up hills. any help would be great

[curtie94]

Well first how many miles.

Does the light come on at idle or all the time?

Have you ever checked it with a mechanical gauge?

At idle the minimum pressure should be 10 and at 3000rpms you should have 50.

[Jarrett]

Have you checked the level since you replaced the oil pan gasket and have put a few miles on it? It's possible you have a leak somewhere.

[oyajicool]

I've said this on other thread which is related to low oil pressure issue.

Since you are using 20W50 already, add a bottle of STP to bump up viscosity and see how it goes with oil pressure issue. If you don't see warning coming on, you have some time to save up for engine rebuild or replacement.

[lilg4mdalbc]

Well do like curtie says and check the pressure first, and like Jarret and check the oil pressure. I would also suggest that if you havent replaced your oil pressure sensor, to change that. Its like 10 bucks, and it could be a faulty sensor that could be throwing you off.

[DjM_coupe]

Check levels and why not use the proper 5w30?

[Tippey764]

20w-50? What the hell? Thats thicker than the stuff you use in big diesel engines

[deevergote]

Why are you running such thick oil?

It's a no brainer. If you suspect low oil pressure, get a gauge and check it. It's really not a difficult concept.
Check your oil level. You changed your gasket, filled it with that too-thick oil, and it was fine... then it wasn't. You didn't say if you looked to see if the oil was low. Too little oil will often result in low oil pressure.

The oil pump is mechanical, so it should be turning as long as the engine is turning. However, it's not unlikely that it could have an internal leak (though this is something I've never dealt with personally, so I'm not speaking from experience.) That could reduce oil pressure. It would be wise to replace that oil pump with a new unit from Honda (that's not something to cheap out on, and you don't need an "upgrade".)

Additionally, it could just be your oil pressure sending unit acting up. Check the wiring to that sensor, near the oil filter. Make sure it's all secure, and not damaged.
Check the oil pressure. If it's good, assume the issue is the sending unit, and replace it. It's not difficult.

[Sordz]

Check levels and why not use the proper 5w30?

Because 20w50 will give him more oil pressure. I'd check it with a mechanical gage but if it's still low running that oil then it's too far gone. Good luck hope it's just a sensor or something.

[oyajicool]

Below is a copy of Honda service manual. According to this, 20W50 is one of recommended engine oil grade. Owner/operator can select this oil based on ambient temp. If using less viscous oil makes oil pressure warning light to come on when engine is at normal operating temp and low rpm, owner/operator can select higher viscous oil.

Installing pressure gauge is good idea but I don't think it is necessary. If faulty oil pressure switch is suspected, change the switch with new (known-good) unit. This is much more economical.

If the wire to oil pressure switch is faulty, there is no warning light come on when ignition switch is set to on position. The wire must be finding a source of ground to have the warning light coming on.

If oil pressure warning light is coming on due to low oil level, the warning light remain on no matter what rpm your engine is doing. The engine will be toast in no time.

[StocK-CB]

the light wouldnt turn on when the engine was cold. it would turn on when the engine would be warm, so when the oil would get thinnner. it has 186k miles, and no i have never checked it with a mechanical gauge. my teacher knows everyhtin there is to know about any car. he was a master technician at a ford/mercury dealership for decades. he knows what hes talkin about. and he said that when the oil light turns on on the stock oil pressure sensor, it is really low on pressure. he said it was probabaly the oil pump and if it was then the engine is probaably done with.. since the oil pump couldnt get the oil up into the spaces to lubricate them.

oh and the oil light would turn off when i would take off
(and yes it had the right oil levels)

[oyajicool]

I wonder what kind of help you were seeking when you made your first post here when you have such knowledgeable shop teacher behind you?

[StocK-CB]

well right now its running fine.... i have been researching the dsm setup u can pu on it, so im thinkin about rebuilding it and doing the setup...
p.s. im only 17 years old, i dont have much experience troubleshooting problems, im goin to attend my first year in college in a couple months so i could know more parts functions

[deevergote]

Well, you basically just told us that your teacher knows everything, which pretty much says you don't accept anything anyone here is saying if it doesn't agree with what your teacher says.

So please, stop wasting our time. Talk to your teacher, do exactly what he says, and hope he's as smart as you believe he is. Good luck.

[reklipz]

I don't have a teacher, and I didn't feel like starting a new thread. Mind if I tack it on here?

Car has 223k miles, got it in the Fall w/ oil pressure light flickering on start and steady when driving. Previous owner said he replaced the unit, but the new one must be bad. I changed the oil about a month ago and changed the oil pressure sending unit; I used RTV Black on the last few threads and the flat surface. The oil pressure light shut off. A few days later, I fixed a transmission leak and "cleaned" the engine bay with Gunk degreaser and water. I drove it about ten miles, and then I accelerated decently hard, and the light came back on and has been on since.

When I start the car, cold or warm, the light is "dim." After a minute or two, the light starts to flash between "bright" and "dim." I used 5W30 oil (I believe, it's possible it's 10W30, I'll have to check). The oil level is between the two lines. The engine has a decent oil leak that I have yet to pinpoint; I think it's under the timing cover.

I went today to buy or rent an oil pressure test gauge, but I wasn't sold on the Harbor Freight one, and O'Reilly Auto didn't have one to rent or buy (not that I would have, they wanted $180...). I will check the pressure once I find a tester (suggestions welcome).

I drive the car daily about 10 miles, and have been since I got it. I'm rather worried after reading the posts above about driving with the light on, but I would think that if it was "really bad oil pressure" I would have noticed serious engine problems by now. What do you all think?