PDA

View Full Version : Troubleshooting low oil pressure light



Stitch
05-12-2009, 08:06 AM
About a week ago my low oil pressure light came on. At first it came on flashing, then when I pulled over and restarted the car it stayed off untill I made it home.
My car is an 88lxi and only has 122,000 miles on it so I am reluctant to believe that it actually has an oil problem, Plus I know the previous two owners ( I am the third owner) and they were very good with keeping up on maintenance. With that in mind I figured the sensor was bad or the wire is corroded.

First thing I found was the plug going to the sensor was very lose, so I crimped it down with a pair of pliers and now it snaps onto the sensor like it should. Took it for a spin and no light, but about a week later the oil light comes on again.

Next I replaced the oil press sensor, restart the car and the light stayed off for another couple days then came back on.

Now I'm starting to wonder what is going on, I know an aftermarket oil pressure gauge would show what's going on but I don't have one yet because I cant find a BSP-NPT bushing

Is this a common problem with 3geez's?
Any suggestions?

conozo
05-12-2009, 12:02 PM
Could possibly be a stuck pressure relief valve. I'm not positive on that, but i beleive it could cause low oil pressure when everything else has been taken care of.

I would not drive it until you get an actual reading on the oil pressure since when the oil light comes on in the dash, it usually means that you are only at a couple psi.

lostforawhile
05-12-2009, 12:31 PM
About a week ago my low oil pressure light came on. At first it came on flashing, then when I pulled over and restarted the car it stayed off untill I made it home.
My car is an 88lxi and only has 122,000 miles on it so I am reluctant to believe that it actually has an oil problem, Plus I know the previous two owners ( I am the third owner) and they were very good with keeping up on maintenance. With that in mind I figured the sensor was bad or the wire is corroded.

First thing I found was the plug going to the sensor was very lose, so I crimped it down with a pair of pliers and now it snaps onto the sensor like it should. Took it for a spin and no light, but about a week later the oil light comes on again.

Next I replaced the oil press sensor, restart the car and the light stayed off for another couple days then came back on.

Now I'm starting to wonder what is going on, I know an aftermarket oil pressure gauge would show what's going on but I don't have one yet because I cant find a BSP-NPT bushing

Is this a common problem with 3geez's?
Any suggestions?
i'll give you the info on the bushing later, msc direct has them, i wonder about the oil pressure light control circuit, i have never figured it out,why in the crap the light blinks i have no idea, any other car it's a simple circuit, sensor detects low oil pressure grounds,light comes on.

petey882
05-12-2009, 01:37 PM
just a question have you checked the oil level??? sometimes low oil level will make the light come on

Dr_Snooz
05-12-2009, 07:39 PM
just a question have you checked the oil level??? sometimes low oil level will make the light come on

That was my first thought too. Please tell us that you checked the oil!

If you burn up an well-tended, low-mileage, stock 3g engine by running it out of oil, I will find you, tie you down and poke boogers into your mouth until you scream "I'm a tool!!!!" loud enough for the neighbors to hear. Then I'll take your car away from you.

Stitch
05-12-2009, 07:55 PM
i'll give you the info on the bushing later, msc direct has them, i wonder about the oil pressure light control circuit, i have never figured it out,why in the crap the light blinks i have no idea, any other car it's a simple circuit, sensor detects low oil pressure grounds,light comes on.
From my understanding when the oil pressure is low the light stays on, then when/if the motor builds pressure the light continues to flash till the ignition is shut off. I hear ya though, seems like they over complicated a pretty simple warning light/circuit
I did some more testing tonight and am almost positive it is either the wire or the circuit. Its a single wire sensor, so it grounds through the sensor and when the circuit is grounded the light should be off, if the circuit is broken the light should come on, correct me if I'm wrong. Anyway, I pulled the wire off the sensor and started the car and the oil light is on. I shut the car off, ran a jumper from the wire to the negative battery post started the car and the light is still on. Tomorrow I'm going to get out my voltmeter and check for continuity, Guess I'm finally going to break down and buy a haynes manual so I'll have some wiring schematics.
The car has enough oil, it has a very slow leak but I check it regularly. That was actually the first thing I checked after the light came on.

Stitch
05-12-2009, 08:07 PM
That was my first thought too. Please tell us that you checked the oil!

If you burn up an well-tended, low-mileage, stock 3g engine by running it out of oil, I will find you, tie you down and poke boogers into your mouth until you scream "I'm a tool!!!!" loud enough for the neighbors to hear. Then I'll take your car away from you.

LOL, first thing after the light came on I found a gas station nearby and checked the oil.
The car is a peach, no dents aside from two or three door dings, the interior is clean and has no stains. The AC blows ice cold, the original owner even took it to Honda to have it converted to r134a.
IF, and thats a big IF, I blow the motor Ill use the opportunity to rebuild it and slap a turbo on it.

lostforawhile
05-13-2009, 11:27 AM
From my understanding when the oil pressure is low the light stays on, then when/if the motor builds pressure the light continues to flash till the ignition is shut off. I hear ya though, seems like they over complicated a pretty simple warning light/circuit
I did some more testing tonight and am almost positive it is either the wire or the circuit. Its a single wire sensor, so it grounds through the sensor and when the circuit is grounded the light should be off, if the circuit is broken the light should come on, correct me if I'm wrong. Anyway, I pulled the wire off the sensor and started the car and the oil light is on. I shut the car off, ran a jumper from the wire to the negative battery post started the car and the light is still on. Tomorrow I'm going to get out my voltmeter and check for continuity, Guess I'm finally going to break down and buy a haynes manual so I'll have some wiring schematics.
The car has enough oil, it has a very slow leak but I check it regularly. That was actually the first thing I checked after the light came on.
no if the oil pressure is low the sensor grounds, if you disconnected the wire from the sensor and it's on then it's the control circuit, think big gray box behind where the center console is. also controls your side markers.

Dr_Snooz
05-13-2009, 08:49 PM
LOL, first thing after the light came on I found a gas station nearby and checked the oil.
The car is a peach, no dents aside from two or three door dings, the interior is clean and has no stains. The AC blows ice cold, the original owner even took it to Honda to have it converted to r134a. It passed TX emissions inspection without any issue.
IF, and thats a big IF, I blow the motor Ill use the opportunity to rebuild it and slap a turbo on it.

Oh, thank God! I'd start by looking in three different places, the pressure sender connection is the first, but you checked that. You might consider replacing the sender though. Second, I'd check the oil filter. If you are running some trash from Fram or the like, throw it away straightway and replace it with a Wix/Napa Gold. I had somewhere near 5 lbs. of oil pressure when I ran a Purolator. That got pitched in the trash real quick. Replaced it with a Wix and it's back at 60. Third, I'd check the oil pump seals. They get old and brittle and the pump loses pressure. If you have oil leaking from under the timing cover, it's time to get in there and replace all the seals. Might as well change the timing belt while you're there.

I would avoid driving it until you figure out what the pressure actually is. That light comes on at some ridiculous level like 3 psi. If it's on and not malfunctioning, then it won't be long and you will be getting that turbo you want.

Rendon LX-i
05-13-2009, 09:35 PM
....that or a bad oil pump...its wierd how you have that low of oil psi....what kind of oil you using...Its a funny question...my car was low on oil pressure for the fact i had crappy oil LOL...

AZmike
05-14-2009, 08:02 PM
A hard left turn can move the oil away from the pick up in the sump for a few seconds--long enough to get the light to flash. Were you driving straight when the light came on?

lostforawhile
05-14-2009, 09:09 PM
if you disconnected the wire at the sender and the light is still on, then it's the module or that wire is grounded somewhere. the oil pressure sensor grounds to indicate low pressure, with it disconnected the light should never be on.

Oldblueaccord
05-16-2009, 09:29 AM
Put a oil pressure guage on it and see where you oil pressure is at. I dunno about the BSP_NPT thing I used NPT always have. Teflon tape it two layers, good clean layers, wound the correct direction never had any problems. I connect mine to the oil filter housing but there might be another port some where thats easier to work on.


wp

lostforawhile
05-16-2009, 09:34 AM
the port for the oil pressure gauge is 1/8 bsp, it's one thread difference then 1/8 npt,you can screw in a 1/8 npt but it will damage the threads, the adaptors aren't that expensive. if he disconnects the wire from the oil pressure sender and the light stays on, then he have an electrical problem. with the wire disconnected you shouldn't have a light,but if you ground the terminal, the warning light should come on,he already said he disconnected it and the light stays on,so it's an electrical problem.

Oldblueaccord
05-16-2009, 09:47 AM
For me I would verify I have oil pressure and worry about the idiot light coming on last but thats my thinking.

As far as the BSP NPT debate its a 5 degree differance and at an 1/8 inch size using a brass its 90% effective for what he's doing. We are not trying to land a guy on the moon just checking to see if he has proper oil pressure. I think that low pressure switch is like set at 10 psi or 7. Thats way too low running down the road.


wp

lostforawhile
05-16-2009, 09:54 AM
you should be able to find the wire coming from the sender in the plug that plugs into the combination control,the big gray box in the center of the car under the dash, under the radio area, should be yellow with red or yellow with black,look at the wire at the sender, unplug that connector and see if the wire coming from the sender has grounded itself somewhere, with the wire at the sender unplugged.

lostforawhile
05-16-2009, 09:56 AM
For me I would verify I have oil pressure and worry about the idiot light coming on last but thats my thinking.

As far as the BSP NPT debate its a 5 degree differance and at an 1/8 inch size using a brass its 90% effective for what he's doing. We are not trying to land a guy on the moon just checking to see if he has proper oil pressure. I think that low pressure switch is like set at 10 psi or 7. Thats way too low running down the road.


wpthe switch is set at 3 psi, scary huh? i tied into the oil pressure adaptor and run a remote pressure switch and lines going to my gauge, i'm using a universal pressure sender switch set at 20 psi.