Alright guys, hoping someone can help me or at least send me on the right path. In the interest of being thorough this will be a somewhat long winded post so hang in there.

I have a 95 Teg LS and out of nowhere my CEL and Oil light popped on. I instantly stopped and noticed my idle was 1500rpms, dead on, no more no less, and wasn't budging. Other than that nothing was out of the ordinary, no signs of low oil pressure.

I had to get the car home, so knowing the risks I said screw and drove it home (which is a 15min drive, including the freeway so speeds of 65+). I got home with no issues, no overheating, no knocking, no tapping, etc. so clearly my motor wasn't toast at this point so it seemed like I might not have the low oil pressure it takes to trip that light.

In the interest of saving time I'll list the key points and highlights that have taken place over the last couple of days:
- oil was a bit high so I drained a little and the lights stayed away for 2 days before returning
- turning the car off then back on clears the CEL, oil light, and returns the idle to normal ( so I have no idea what the cel is)
- I've driven the car about 15mins 3 different times with the lights on and the motor still sounds quiet (so I don't see how low oil pressure could be the cause as it should of self destructed by now)
- I have since replaced the oil and filter (running an oem honda filter), dropped the oil pan (everything is clean with no blockage), and replaced the oil pressure switch with a new oem one.

So after all that I'm still getting the lights and idle problem but the car sounds, acts, and drives like normal. I haven't checked the actual pressure yet b/c I don't have access to a tester and really didn't want to spend the money on a gauge and go through the hassle of installing it ( this is just my daily driver ).

So if anyone has came across anything similar please shoot me some pointers / ideas. I'm really curious about what the CEL could be, and why its affecting my idle.

Anyways, thanks for any help you guys can give.

 

The very first thing I would do it check the CEL code. I'm wondering this is the nicest way possible, why didn't you check it? Its free, and takes 15 seconds.


Check the code and let us know! :D

In case you don't know how, there is a blue plug under the passenger side kickpanel (near the door) and it is in a green rubber harness. Take it out and jump it with a paperclip, and read the code.

Look at your CEL light

1 long blink = 10
1 short blink = 1

Then read the code up.

sebteggy

 

1. check the code(s). first and foremost.
2. check your oil pressure manually with a gauge. you must confirm that you're getting adequate pressure. it's kinda important

 

http://check-engine-light-codes.blog...retrieval.html

 

I know how to check the code but like I said as soon as you turn the car off it clears the code. So using the jumper wire on the blue plug method doesn't work.

As for oil pressure I hadn't checked it yet bc I didn't want to go buy a gauge and install it if I didn't have to. That's why I was seeing if anyone had any ideas first BUT I was getting no where so I jut finished installing one. Here's the results (at normal operating temp):
- idle = 12-15psi
- at 3k = 60-70psi

I can't remember exact numbers that's why there's a variant. The light never kicked on during my drive and I'm using a mechanical gauge so there's nothing to skew the numbers.

 

You don't have to turn the car off to check the code.

 

The only way Ive done it is to shut the car off insert the jumper wire turn the key to the on position and count the flashes. Whats another way of doing it, short of tracking down an obd 1 scan tool?

Of course after I installed thr gauge at my parents I drove the car home and had no lights and great oil pressure so I dont even know if the light will come back on.

 

OK, I'm wrong. When I drove an ODB1 car I just left it running and jumped the connector but, my friend is now telling me that it could damage the ECM. So, dis-regard what I said.
---------------------

My first instinct says you have a clog in the oil system but, with the engine running fine I think you may have an intermittent short in the oil pressure sensor circuit. Disconnect the oil pressure sensor and look for a bad connection or wire. Then test for reference voltage on the harness side of the connector.

 

I thought about there possibly being a short. I checked the wire but didn't see any obvious breaks in it. I haven't tested for voltage yet (just found my multimeter). Is that a 5v sensor?

I just find it hard to believe I've actually had a low oil pressure situation. I've personally never heard of a car going back and forth from low oil pressure to normal just randomly. But I suppose anything is possible.

Thanks for the input.

 

Just check the code. The ECU stores it even if the car is off

sebteggy



EDIT: Do you have any leaks? How often do you have to top off your oil?

 

Sorry, with the engine at operating temp you should be 10psi minimum at idle and 50psi minimum at 3000rpm. You're good on that. That's why I'm leaning towards a short. Intermittent short because it clears when you turn it off and comes back after a while.

Don't quote me but, I think that's a 5V reference.

BTW: I was just reminded in another thread that dielectric grease for connections works wonders sometimes.

 

unplug the the sender. if the light stays off while driving, the problem is the sender. if it comes on at all with it unplugged, problem is wiring

 

There's no code being stored. It was the first thing I tried. From my past experience the ecu only stores "hard" codes and "soft" ones get cleared. As for oil, no leaks. I never have to top my oil off... Pretty impressive for a 200k car lol.

I can try unplugging the sensor to check the wiring but I know the sensor is good because I've swapped it out (with an oem one) and I've had the lights come both before and after.

So right now I have good oil pressure and no lights on. I'm just going to drive it and see if the light kicks on and see where my oil pressure is at when it does. That will at least confirm that I don't have a serious low oil pressure issue.

As a side note I've been told when these cars trip an oil light it also kicks the cel on at the same time and raises the idle in hopes of bringing the oil pressure up. Can anyone else confirm this? Seems logical since our oil pressure is directly related to rpms.

 

^ Possibly

Your best bet is to just carry a paperclip with you and as soon as the code comes back, check it and let us know.

Other than that, I have never heard of 'soft' and 'hard' codes. Cool

 

I can't check the code. I've said that a few times (not trying to be a dick). Every time I shut the car off the code clears... and I'm only aware of pulling obd I codes by shutting the car off, inserting the jumper wire, turning the key to the on position, and counting the blinks. If theres another method (other than an obd I scanner) then I'm all ears because I've never came across it and it would be rather helpful.

As for the soft / hard code, I've always heard of soft codes clearing when the car turns off (usually a less serious cel) and a hard code will stay in the ecu until manually cleared. Maybe people don't refer to it as that anymore, I dont know? I don't think it applies to obd II because those things have cel's for everything, and they store all of them. Hell I don't know how many times I've gotten a cel on my S2K because the gas cap isn't tight enough.

 

you can't retrieve trouble codes on obd2 cars at the 2 pin connector. you have to jump 2 of the pins off the diagnostic port.
or apparently another way is to cycle the key on and off in a specified sequence.
google it. you'll find the instructions.
or autozone scans for free, don't they?

and a hard fault means the code is tripped as soon as the key is cycled on and ecu runs the vehicle self test on all the inputs.
soft faults take driving cycles to occur. but they should still be stored, unless cleared either by disconnecting the battery (on some models), removing the ecu fuse, or clearing them through a scan tool.

 

My car with the issues is an obd I car (1995 Integra). I'm fully aware of how to pull codes. My issue is everyone keeps telling me to use a jumper wire (which I know how) except every time I turn the car off the codes clear, and I'm not aware of how to check it with out turning the car off first. Thats how I got into the soft / hard codes (b/c the ecu isn't storing the coe), and I was just comparing obd I to II.

 

oh ****. my bad. went right over my head. still though, soft faults should be stored in the memory.
ok, let's try this; run the vehicle and disconnect the iacv. wait for the cel to illuminate. once it does, shut it off and see if you can retrieve the code

 

what exactly occurs when you check the code? does the cel come on at all?

 

Nope, nothing. The lights come on and then shut of like normal, no blinking. Then if I start the car up theres not cel, it's completely clear. Thats why I'm starting to think it could be what I mentioned earlier. That being when the oil light is tripped (for w/e reason) it automatically kicks the cel on and raises the idle to 1500rpm in hopes of raising the oil pressure (not sure if thats what is happening but someone told me it could be, and it seems logical). The reason I'm starting to think that is because its not saving the code and the cel only kicks on when the oil light does, and the idle shoots to 1500 at the exact same time.

 

so when you check the code, it's not a solid cel though, right? the light just goes out?
and did you try inducing a hard fault, unplugging the iacv and checking to see if that sets a code?

 

Leave the car running. Ive checked codes with my car running many times without problems.

Why would this be a danger? I don't get it, where did you hear this?

 

I just got home from driving the car and about 45secs into my drive the lights kicked on. Good thing is my oil pressure was solid. 60-70psi at 3k rpms on the freeway (started dropping a little as the car warmed up) and about 25psi at idle (the car was idling at 1500rpm bc the cel was on).

When I shut the car off after the lights kick on and then instantly start it back up everything is cleared that quick. The lights come on then go off when you turn the key to the on position... Just like it should. Start the car and there are no lights.

I haven't had a chance to induce a hard code yet. It's looking more like its an electrical issue in the wiring. Which would be odd because I haven't touched any wiring, by accident or on purpose.

@sebTeggy, how have you checked a code on an obd l car while it's running without using a scanner?

 

when you jump the service connector, is it a solid cel? or just nothing?

 

It's nothing.