1987 accord lxi hatchback oil light flashin an pgmfi light

[tylerpitts]

My 87 hatch oil light us on when I crank it an when I accelerate the oil light starts flashin anyone no about that? Also pgmfi lights comes on after motor temp is a quarter way up an throwin a code 6

[lostforawhile]

the light flashes when you get a temporary drop in oil pressure, it will flash and stay flashing until you turn off the key, if the oil light comes on and stays on, then the oil pressure stays low, you need a way to verify oil pressure, it could be something as simple as a failing oil pressure switch, to something as serious as bad bearings etc

[gp02a0083]

it is somewhat normal for the oil light to come on and stay lit for a few seconds after starting,but really no more than 3 seconds i'd say. However when driving and the oil light comes on and flashes is a good concern. Start with the basics and check the oil level, if that checks out then move onto the sensor. When the light flashes its indicating low oil pressure, stays lit is very low to no oil pressure. You can measure the oil pressure if you have a gauge with a 1/8 BSP 28 threads per inch adapter you can check the oil pressure. At that point your removing the sensor anyway and they are cheap so just replace that. Make sure to use liquid high temp thread sealer rather than the PTFE tape. If replacing the sensor does not resolve the issue then you may have a oil pump problem.

Code 6 is typically a coolant temperature sensor or wiring related to it. Easy to diagnose, it is located on the thermostat housing. I suggest using a multi meter or ohm meter to measure the resistance of the sensor when it id dead cold, say ambient temperature is around 70F should have a measurement around 2.5 ohms give or take 1 ohm. when the car is hot and at operating temp the resistance should be lower than 0.5 ohm

[tylerpitts]

Thanks for the info i hope its just the sensors.

[lostforawhile]

Thanks for the info i hope its just the sensors.

I hope so too, they do tend to get old and leak oil into the contacts,which can cause this, very common on most cars. It's only one switch on top of the oil filter housing. there will be a big rubber boot over it, normally at this age, it's pretty disintegrated, so you may be able to just tear off the boot. it will work fine without it. The box under the radio , along with a bunch of other functions, when the engine is running it detects 12 volts from the alternator charge light wire, when it does, it arms itself, then any brief drop in oil pressure will trigger a circuit which will flash the oil pressure light. This is so you are aware of brief drops that might not be long enough to light the light, low oil level can cause this

[gp02a0083]

I hope so too, they do tend to get old and leak oil into the contacts,which can cause this, very common on most cars. It's only one switch on top of the oil filter housing. there will be a big rubber boot over it, normally at this age, it's pretty disintegrated, so you may be able to just tear off the boot. it will work fine without it. The box under the radio , along with a bunch of other functions, when the engine is running it detects 12 volts from the alternator charge light wire, when it does, it arms itself, then any brief drop in oil pressure will trigger a circuit which will flash the oil pressure light. This is so you are aware of brief drops that might not be long enough to light the light, low oil level can cause this

The oil pressure switch is a single 1 wire connection and its placement would only allow oil leaking from the valve cover or the base housing to possibly come in contact with it. There are no external contacts other than the single wire that comes off of the sensor that is technically a simple transducer. If the system falls below the factory set safety pressure value for more than 10 seconds it will continually flash and will only stop flashing when the ignition switch is turned off. Total loss of pressure will keep the light on. The system is primed from the Alternator cranking signal from the voltage regulator (pin L Wht/Blu wire only), the charge light shunts the IG and L pins off the voltage regulator (Wht/ Blu and Blk/Yel)

[lostforawhile]

The oil pressure switch is a single 1 wire connection and its placement would only allow oil leaking from the valve cover or the base housing to possibly come in contact with it. There are no external contacts other than the single wire that comes off of the sensor that is technically a simple transducer. If the system falls below the factory set safety pressure value for more than 10 seconds it will continually flash and will only stop flashing when the ignition switch is turned off. Total loss of pressure will keep the light on. The system is primed from the Alternator cranking signal from the voltage regulator (pin L Wht/Blu wire only), the charge light shunts the IG and L pins off the voltage regulator (Wht/ Blu and Blk/Yel)

I'm talking about pressurized oil leaking into the switch contact internally, it's only a rubber diaphragm in there. you are making the wiring sound more complex then it is, the blue and white white changes state from a ground to 12 volts when the alternator is charging, this is your signal to the box to arm the system. the blue and white wire works the same on both carbed and FI engines, and it's not supposed to be ten seconds, it's supposed to be immediate when there is any drop that would turn on the light, but is too short of a duration to do so

[gp02a0083]

I'm talking about pressurized oil leaking into the switch contact internally, it's only a rubber diaphragm in there. you are making the wiring sound more complex then it is, the blue and white white changes state from a ground to 12 volts when the alternator is charging, this is your signal to the box to arm the system. the blue and white wire works the same on both carbed and FI engines, and it's not supposed to be ten seconds, it's supposed to be immediate when there is any drop that would turn on the light, but is too short of a duration to do so

factory spec is 10 seconds, and if you insist here it is right from the factory manual



the only part of that statement i'm agreeing with is that the system uses the wht/blu ( not to be confused with your favorite wht/blue for the charge light) and goes to the integrated control unit for both PGMFI and Carb'd models and specifically on the carb'd models to the choke heater + emission control

I do not agree with the statement that the system is armed when the alternator is charging and i have verified this with my own 3rd gen and I have been kind enough to include a video for you. From my simple test it would seem that the system is armed when switched to the +12V source even when the alternator is not charging

http://vid1008.photobucket.com/album...ps16997222.mp4

[lostforawhile]

factory spec is 10 seconds, and if you insist here it is right from the factory manual



the only part of that statement i'm agreeing with is that the system uses the wht/blu ( not to be confused with your favorite wht/blue for the charge light) and goes to the integrated control unit for both PGMFI and Carb'd models and specifically on the carb'd models to the choke heater + emission control

I do not agree with the statement that the system is armed when the alternator is charging and i have verified this with my own 3rd gen and I have been kind enough to include a video for you. From my simple test it would seem that the system is armed when switched to the +12V source even when the alternator is not charging

http://vid1008.photobucket.com/album...ps16997222.mp4

I have the factory electrical service manuals, the same wire for the light is used as a signal, this keeps the light from flashing before the car is started, It's also used as power for the choke on carb cars, The regulator switches field rapidly between 12 volts and ground to regulate voltage, when the alternator quits charging that wire is ground to operate the charge warning lamp, when it is charging it shows 12 volts, which is also a signal to the box etc, this indicates the engine is turning is all

[gp02a0083]

I have the factory electrical service manuals, the same wire for the light is used as a signal, this keeps the light from flashing before the car is started, It's also used as power for the choke on carb cars, The regulator switches field rapidly between 12 volts and ground to regulate voltage, when the alternator quits charging that wire is ground to operate the charge warning lamp, when it is charging it shows 12 volts, which is also a signal to the box etc, this indicates the engine is turning is all

See 10 seconds according to factory manual.
ok apparently you didn't see my video and fail to answer the question and yes I have the full factory service manual as well. Take a look at 25-102 and review the 25-103 I displayed in a previous post. What keeps the oil light from flashing prior to start up is the zero pressure it measures as it should when not running or when total oil pressure is lost. The signal wire only comes into play AFTER the system is primed and reaches an intermediate pressure value that is between the set value and 0.

this is your signal to the box to arm the system.

This signal wire is a reference wire, it does not arm the system, the system is armed when the ignition is switched to IGN1. The literal label for this wire is Wht/Blu2

[88Sleeper]

Hey tyler, if you replace, unplug the sensor first since the plug is plastic, and then use a 1 1/8" (or so) wrench to get it off. It will be a pain because a wrench that big barely fits without hitting the firewall.

I used one with a straight end, had to turn a little, flip it over, turn a little, flip it over, etc to get it out. Give it some patience.

I got a sensor from napa for $13 or so. I recommend the sealant primer from permatex as well.

If you see oil on the back of the block, you might need the oil filter base gasket done as well.
It costs $6-8 from Honda, & they still stock em. Since you have to take the sensor off to get to the filter base bolt behind it, I suggest you do both if you feel you need it.

Also, clean the bypass valve if you do take the filter base off. It is easy, and lightly sand the tube plug auth someemery paper if you see that the surface is scratching up (and flip this surface upside down in the tube when reassembling, lol)

Have you done anything with the oil pump at all?

[lostforawhile]

See 10 seconds according to factory manual.
ok apparently you didn't see my video and fail to answer the question and yes I have the full factory service manual as well. Take a look at 25-102 and review the 25-103 I displayed in a previous post. What keeps the oil light from flashing prior to start up is the zero pressure it measures as it should when not running or when total oil pressure is lost. The signal wire only comes into play AFTER the system is primed and reaches an intermediate pressure value that is between the set value and 0.



This signal wire is a reference wire, it does not arm the system, the system is armed when the ignition is switched to IGN1. The literal label for this wire is Wht/Blu2

according to my manual, which is the 86 electrical troubleshooting manual, once it detects +12 volts from the charge light wire, then 30 seconds later it arms, if it detects the oil pressure switch closing for more then .5 seconds after that, and then reopening, it will flash the light until the ignition switch is turned off. are you saying it won't flash for more then ten seconds after a drop in pressure? that would defeat the purpose, it's supposed to flash to show you drops in pressure too quick to see with the light, according to the electrical manual the white/blue which is the same wire for the light, and on the carb car the choke heater, is listed as engine running input. It's like most charging systems, it changes state from a ground to a positive 12 volts when the engine is running, when the box detects 12 volts from that wire, 30 seconds later it arms. It may be a shorter time on later models. The warning light wire is that simple, when the alternator is charging, you have 12 volts on both sides of the bulb, and no ground, when it's not charging you you 12 volts from ignition and now you have a ground, that same 12 volts when it's charging is what triggers the integrated control box and arms the flasher circuit.

[lostforawhile]

it's done this way for a reason, if you are sitting in the car and have turned the key to ignition, but havent started the car, it won't start timing until it detects the engine is turning, they could have also done this with the AC delay box as it detects RPMs, or even the fuel safety relay on carb cars, or fuel pump circuit on FI cars, but they chose to use the alternator wire

[tylerpitts]

Well I think that sensor caused me to twist a rod up like tornado .is there anyway I can swap the a20a3 with a f23a I have in a wrecked accord

[lostforawhile]

Well I think that sensor caused me to twist a rod up like tornado .is there anyway I can swap the a20a3 with a f23a I have in a wrecked accord

what happened low oil pressure?

[gp02a0083]

what happened low oil pressure?

a twisted rod in a thread where discussion of the oil light flashing under acceleration lol

[lostforawhile]

a twisted rod in a thread where discussion of the oil light flashing under acceleration lol

obviously it had something to do with oil pressure, but no one ever specified if it was staying low or not, no one ever even verified if it was low or not, or a bad switch, which now of course we know it actually was low