Oil Light Problem

[ToyotaVanNut]

Hi again!

I just thought I would ask this, which so far has not proved to be a problem but I hope I'm not secretly hurting the van!

Occasionally, mostly when idling (I think), the oil light in the van (1984 2WD) will come on. The oil pressure has been tested numerous times and the oil pressure is good. Also the sensor has been replaced twice!

Due to this, it was taken to a professional mechanic. He simply said that it would come on when idling, but to not worry because the pressure is fine. I am a little worried still/skeptical.

I just want to ask people who have a lot of experience, AKA the wonderful forum if any of you have ever experienced anything like this or know what it could be?

Any insight is beyond appreciated and helpful.

Add. info: Oil used - 10w30 "AutoZone" brand. Oil is full when dipstick is checked as well

THANK YOU! :)

[timsrv]

Depending on the trim level of your van, you may have 2 oil lights. One is amber and illuminates when the oil level is low. The other is red and illuminates when pressure is low. If it's the amber one and you've verified the correct oil level, then it's a bad level sensor (driver's side middle of oil pan). This is a common problem on the van & most vans I own have had this problem. It can be fixed, but if you have a regular routine for checking & changing oil, assuming it's never low, then you may wish to simply ignore it.

If it's the red light then it could be due to low or no oil pressure (that sending unit is on the passenger side under the oil filter). That sender provides a ground to the oil light and is "normally closed". When pressure reaches 4-5 psi, it "floats" the contacts inside that switch. When the contacts float, the ground contact is lost (circuit opens), & the light goes off. Your oil pump moves oil from the sump, past that sender, through the filter, then out to the bearings, lifters, etc. New engines build higher pressure because the bearings are tight & the oil has trouble escaping past them. As the bearings wear there is more room for oil to escape & pressure is reduced. Oil pumps have the lowest output at an idle & oil is the thinnest when hot. Taking all this into account, a worn engine at an idle while hot may not be able to maintain enough oil pressure to keep the oil sender from grounding out. As long as it only does it at a hot idle it's not anything to worry about. While at an idle the engine is not stressed and it does not need as much oil pressure. You can just ignore it or start using thicker motor oil (10w-40 or 15w-40 would be fine). I've heard of guys using 20w-50, but IMO that's too thick. I'd only go that thick if I were trying to prolong the demise of an engine with a mild knock.

My 89 van was giving me intermittent low pressure warning at odd times. Often it was at higher RPMs or when the engine was cold. This concerned me so I installed an aftermarket oil pressure gauge. I was quickly able to determine that it was a problem with my warning light circuit. I tried changing the switch/sending unit, but that made no difference. Based on that I figured it had to be the wire in the harness (between the sender & the gauge) grounding out someplace. I performed a careful & thorough inspection of my harness (at least the parts I could see) but could not find the bad spot. I ended up running a new wire from the sender to the gauge and that solved my issue. Tim

[ToyotaVanNut]

Depending on the trim level of your van, you may have 2 oil lights. One is amber and illuminates when the oil level is low. The other is red and illuminates when pressure is low. If it's the amber one and you've verified the correct oil level, then it's a bad level sensor (driver's side middle of oil pan). This is a common problem on the van & most vans I own have had this problem. It can be fixed, but if you have a regular routine for checking & changing oil, assuming it's never low, then you may wish to simply ignore it.

If it's the red light then it could be due to low or no oil pressure (that sending unit is on the passenger side under the oil filter). That sender provides a ground to the oil light and is "normally closed". When pressure reaches 4-5 psi, it "floats" the contacts inside that switch. When the contacts float, the ground contact is lost (circuit opens), & the light goes off. Your oil pump moves oil from the sump, past that sender, through the filter, then out to the bearings, lifters, etc. New engines build higher pressure because the bearings are tight & the oil has trouble escaping past them. As the bearings wear there is more room for oil to escape & pressure is reduced. Oil pumps have the lowest output at an idle & oil is the thinnest when hot. Taking all this into account, a worn engine at an idle while hot may not be able to maintain enough oil pressure to keep the oil sender from grounding out. As long as it only does it at a hot idle it's not anything to worry about. While at an idle the engine is not stressed and it does not need as much oil pressure. You can just ignore it or start using thicker motor oil (10w-40 or 15w-40 would be fine). I've heard of guys using 20w-50, but IMO that's too thick. I'd only go that thick if I were trying to prolong the demise of an engine with a mild knock.

My 89 van was giving me intermittent low pressure warning at odd times. Often it was at higher RPMs or when the engine was cold. This concerned me so I installed an aftermarket oil pressure gauge. I was quickly able to determine that it was a problem with my warning light circuit. I tried changing the switch/sending unit, but that made no difference. Based on that I figured it had to be the wire in the harness (between the sender & the gauge) grounding out someplace. I performed a careful & thorough inspection of my harness (at least the parts I could see) but could not find the bad spot. I ended up running a new wire from the sender to the gauge and that solved my issue. Tim

First of all, thank you so much for all of this info, it has already helped immensely. My first question is, how would I know if I have two oil lights? I believe there is only one (at least, I've only ever seen one!) Just to be 100% sure here is what it looks like, maybe you can tell me if you know which it is!:

http://postimg.org/image/rxl215ued/
http://postimg.org/image/njche5n35/

I will try to install a pressure gauge to check it! That is a great idea. I think that if that is all good, I should attempt the warning light circuit, right?

I have also noticed that it is not exclusively when idling, sometimes I can't even really point out when it turns on!

Lastly, if the van has only 101,000 miles on it, do you think I should still possibly up it to 10w-40?

You all are the absolute best!!

[timsrv]

I don't think your van has the oil level light (amber). The one showing in your picture is the low oil pressure light (red). I wouldn't switch to a thicker oil until you know what the pressure actually is. If it's low, then you could benefit from a thicker oil. An after market pressure gauge is a good thing to have. Tim

[ToyotaVanNut]

I don't think your van has the oil level light (amber). The one showing in your picture is the low oil pressure light (red). I wouldn't switch to a thicker oil until you know what the pressure actually is. If it's low, then you could benefit from a thicker oil. An after market pressure gauge is a good thing to have. Tim

Tim, thank you so much. I will check with that and let you know! Would you say that if the oil pressure is running at a good level (what would this be, by the way?), that it is most likely circuitry?

[timsrv]

Because the sender establishes a ground for the light (when pressure is low), another way you could check the circuit is to disconnect the wire at the sender, tape off the connector, & then drive the van a few days. If the circuit is good, there is no possible way for the light to come on. If however the light comes on, then you'll know the circuit is shorted some place (like mine was). If that checks out okay, then you may want to install an aftermarket pressure gauge. The idiot light sender is designed to turn on the light somewhere between 4 - 5 psi, so if your pressure is lower than that at a hot idle, and your light comes on, then the low pressure warning system is doing it's job (run thicker oil). High pressure (at cruising speed) will vary, but I would want to see at least 50 psi when the engine is at 3000 RPMs or higher. If you install an aftermarket pressure gauge, here's a thread that should help with the hook-up. Tim

http://www.toyotavantech.com/forum/showthread.php?752-New-guy-wanting-to-say-H-i-and-a-tachometer-question&p=4342#post4342

Here's another thread with good general information regarding the oil pump & related issues: http://www.toyotavantech.com/forum/showthread.php?161-Does-an-Oil-Pump-fail-often

PS: It's unlikely, but a messed-up pressure relief valve (located in the oil pump) and/or a plugged up oil filter can also cause low oil pressure.

[ToyotaVanNut]

Because the sender establishes a ground for the light (when pressure is low), another way you could check the circuit is to disconnect the wire at the sender, tape off the connector, & then drive the van a few days. If the circuit is good, there is no possible way for the light to come on. If however the light comes on, then you'll know the circuit is shorted some place (like mine was). If that checks out okay, then you may want to install an aftermarket pressure gauge. The idiot light sender is designed to turn on the light somewhere between 4 - 5 psi, so if your pressure is lower than that at a hot idle, and your light comes on, then the low pressure warning system is doing it's job (run thicker oil). High pressure (at cruising speed) will vary, but I would want to see at least 50 psi when the engine is at 3000 RPMs or higher. If you install an aftermarket pressure gauge, here's a thread that should help with the hook-up. Tim

http://www.toyotavantech.com/forum/showthread.php?752-New-guy-wanting-to-say-H-i-and-a-tachometer-question&p=4342#post4342

Here's another thread with good general information regarding the oil pump & related issues: http://www.toyotavantech.com/forum/showthread.php?161-Does-an-Oil-Pump-fail-often

PS: It's unlikely, but a messed-up pressure relief valve (located in the oil pump) and/or a plugged up oil filter can also cause low oil pressure.

Tim, I can't thank you enough. That is a very good idea. Maybe I will try taping that off first to determine if that is what it is. I really appreciate the psi info as well as the thread on how to install an aftermarket pressure gaugage, so helpful.

I was going to post a separate thread called "Misc. Tech Questions, but since I have you hear I might as well ask! (lol!) Here are the misc:

1. Recommended tire pressure? (using original rims and standard tire size for the van) (usually carrying nothing too heavy)

2. There is a lot of rust in various places of the van, (esp. the underside). Is there any way to take care of this/strengthen/revitalize the rusted areas? Is there some magic spray or something like that to reinforce/provide longevity to rusting parts?

3. The horn works about 50% of the time, it's a coin flip! Any possible reason/explanation and what I could do to help it?

[timsrv]

For the sake of organization I would request you search the forum 1st, then if you cannot find the answers, post your questions in similar threads or start new ones :thmbup:. Tim

[ToyotaVanNut]

For the sake of organization I would request you search the forum 1st, then if you cannot find the answers, post your questions in similar threads or start new ones :thmbup:. Tim

Will do! Doing right now!

[Jdelgado]

I have a few pending repairs one of them is replacing the oil light sensor. The oil light flashes and stays on briefly here and there but 9 times out of 10 it's a false alarm, Out of precaution I still pull over and check. By any chance does anyone know the part number?

Thank you and Happy holidays!

[Flecker]

I have a few pending repairs one of them is replacing the oil light sensor. The oil light flashes and stays on briefly here and there but 9 times out of 10 it's a false alarm, Out of precaution I still pull over and check. By any chance does anyone know the part number?

Thank you and Happy holidays!


Heres a sening unit/ switch for the oil pressure: https://www.amazon.com/gp/product/B000C81MRA/ref=oh_aui_detailpage_o01_s01?ie=UTF8&psc=1

I installed in mine and it works. Again, reading what Tim wrote above, you may have 2 lights... I don't know the trim level/ gauge cluster of your van. I have an 87 Cargo and only have the red oil indicator in my gauge cluster. It reads not only the oil pressure, but also the oil level via the level sending unit, drivers side of engine, mounted on the oil pan. I would first check to verify BOTH connectors are actually plugged in and greased with some bulb grease/ dielectric grease. The level indicator is especially prone to getting gummed up or the plug dislodged. You will know why when you see it. :yes:

So far as I know the level sending unit is NLA and dang near impossible to rebuild. If/ when I run into that scenario I will either bypass or yank the annoying dummy light and check fluid levels on a regular basis, which I already do!

Another option is to find another 84/85 oil pan without the level sensor cut out and just eliminate the thing altogether... it's also a known LEAK spot in my opinion, best sealed with Toyota fipg.

Take care!

[llamavan]

Another option is to find another 84/85 oil pan without the level sensor cut out [...]

Only the '84 Vans did not have the oil level sensor, and thus the oil pan with no port for the sensor.

Also in case you are thinking of snagging a junkyard sensor, '85 Vans DO have oil level sensors, but they don't interchange with '86-'89 due to exterior differences in the oil pan.

Gwen

[Flecker]

Only the '84 Vans did not have the oil level sensor, and thus the oil pan with no port for the sensor.

Also in case you are thinking of snagging a junkyard sensor, '85 Vans DO have oil level sensors, but they don't interchange with '86-'89 due to exterior differences in the oil pan.

Gwen

Thanks for clearing that up!:thmbup:

[Jdelgado]

Heres a sening unit/ switch for the oil pressure: https://www.amazon.com/gp/product/B000C81MRA/ref=oh_aui_detailpage_o01_s01?ie=UTF8&psc=1

I installed in mine and it works. Again, reading what Tim wrote above, you may have 2 lights... I don't know the trim level/ gauge cluster of your van. I have an 87 Cargo and only have the red oil indicator in my gauge cluster. It reads not only the oil pressure, but also the oil level via the level sending unit, drivers side of engine, mounted on the oil pan. I would first check to verify BOTH connectors are actually plugged in and greased with some bulb grease/ dielectric grease. The level indicator is especially prone to getting gummed up or the plug dislodged. You will know why when you see it. :yes:

So far as I know the level sending unit is NLA and dang near impossible to rebuild. If/ when I run into that scenario I will either bypass or yank the annoying dummy light and check fluid levels on a regular basis, which I already do!

Another option is to find another 84/85 oil pan without the level sensor cut out and just eliminate the thing altogether... it's also a known LEAK spot in my opinion, best sealed with Toyota fipg.

Take care!

Awesome! One more question do you have to have drain the oil to replace this sensor?
Thank you

[Flecker]

Awesome! One more question do you have to have drain the oil to replace this sensor?
Thank you

For the pressure sensor, no not really. It taps into a 10 or 12mm boss next to the oil filter housing. Might want to set a rag or something under it though, it may dripple some when you turn it out.

Unless you have the right size socket for it, your gonna be using some small channel locks just to get the old one out... it's slight cumbersome. I did find with the filter removed it was easier.

[Grappler]

This is SO not worth starting a new thread about but I've discovered yet another bizarre oil light problem.

Now that my van is back to being a long-hauler after an overhaul, I noticed my oil light would intermittently come on during long trips. After determining it wasn't a pressure sensor issue, I started to assume it was the typical level sensor. As I was buzzing down the 5 in the middle of nowhere with only my thoughts and anxieties about the van dumping oil randomly, I even found that jerking the wheel to the left a bit would typically make the light go out (I assumed I was knocking the level sensor unstuck when doing so, returning it to its high "off" position)

Then, it stopped, and I made another assumption that the detergents in the oil had cleaned the shaft enough to prevent it.

BUT THEN. It started again, and when I was again out of podcasts and left to ponder I realized something else -- the light was going on directly in conjunction with my turn signal being activated. .... Okay. So now I'm left to ponder if it's an electrical issue either in the dash cluster (87 cargo, simple one, no clock) or in uh... the steering column? Is an oil sender wire routed through there? Why would it be? Am I just insane and seeing things that aren't there?

I'm not really expecting an answer, just looking for commiseration/to know if anyone else has experienced anything like this, ever.

[timsrv]

Here's a quote from an earlier post in this thread:


If it's the amber one and you've verified the correct oil level, then it's a bad level sensor (driver's side middle of oil pan). This is a common problem on the van & most vans I own have had this problem. It can be fixed, but if you have a regular routine for checking & changing oil, assuming it's never low, then you may wish to simply ignore it.


I've never bothered to troubleshot or fix this issue. As long as you know the oil level is correct, then that system is not needed. If you're the main person who drives the van and you have a routine or system down for regularly checking oil level, then I'd just ignore it. If it really bothers you then you could always remove the light bulb in the dash or perhaps repair/replace that sensor. As you mentioned, it's also possible there's a problem with the electrical system (like a bad ground) but intermittent things like that can be hard to trace. Tim

[originalkwyjibo]

Try this (https://www.toyotavantech.com/forum/showthread.php?2620-Oil-Level-Sensor-issues&p=37150&viewfull=1#post37150)one. Post 39 and 40 discuss a bypass of the sensor. This could be useful for troubleshooting by process of elimination. If you jumper wire the sensor harness and the light still comes on then you know the problem is elsewhere. Like Tim said, grounds are always suspect when multiple systems seem to have problems that are connected. If you jump the harness and the oil light/blinker correlation still exists, then I would want to look at a wiring schematic to see if there is a common ground location between those two systems.

[Burntboot]

I took a quick look at my 88 manual, the non-LE instrument pack indicates that the level sensor and the pressure sensor are married together by the "oil level warning computer" (5 pins), could just be a glorified relay but have not put eyes on.

Anyway, pin 5 of that "computer" connects with ground point C (located on cowl right side)
The T/S flasher and both inst pack indicator bulbs also utilize the same ground point.
I doubt they run 2 separate wires all the way to that cowl ground and is likely an internal harness splice somewhere along the way.
Further, the ign switch feeds the fuse box and both circuits pull from the same power feed (G)
8366
I would think that means that there could indeed be some merit to your observations.
Might be worth pulling things apart, to clean inspect all connectors

[ssocal87]

I picked this up as a solution to the oil level light (yellow one next to O/D light on the dash) but can't seem to locate it. I see the squarish oil pressure part on the driver side. Is this one located elsewhere? Any thoughts ? I am thinking that this may not apply to my model, 87 LE Auto 4wd.
https://www.amazon.com/dp/B0789C7C8R/ref=cm_sw_r_cp_apa_fabc_48SGCYGJ31RK8W2B6QGR

[timsrv]

Different years/trim levels had different warning systems. For 86 - 89, if you have a gauge, then you will not have a pressure warning light, but you will likely have an oil level warning light. If you have a pressure warning light, you probably don't have a level warning light.

[llamavan]

To clarify:

• on all '85 vans and on the '86-'89 cargo and DLX trim levels, there is a single warning light that illuminates for either low pressure or low level
• from '86 on, the LE model has an oil pressure gauge and a small orange-ish LED that illuminates for low oil level only
• some DLX vans also have the LE cluster arrangement (tach, oil pressure gauge, low oil LED); this was an option from the factory

Gwen

[timsrv]

To clarify:

• on all '85 vans and on the '86-'89 cargo and DLX trim levels, there is a single warning light that illuminates for either low pressure or low level
• from '86 on, the LE model has an oil pressure gauge and a small orange-ish LED that illuminates for low oil level only
• some DLX vans also have the LE cluster arrangement (tach, oil pressure gauge, low oil LED); this was an option from the factory

Gwen

Huh..........could it be that all this time I have been misunderstanding the system for 86 - 89 cargo and DLX trim levels? I always thought that was only a pressure light. If it does oil level too, then that could explain the issue I discussed earlier in this thread with my 89 :doh:. I'm not driving that one anymore due to an idiot crashing into me. Sadly, my 86 LE daily driver (which I have been using as a substitute) was destroyed last week by a 16 year old in a Audi. Due to age and increasing rarity, I will likely be replacing it with a diesel Sprinter :cry:. Tim

[Gareth]

I picked this up as a solution to the oil level light (yellow one next to O/D light on the dash) but can't seem to locate it. I see the squarish oil pressure part on the driver side. Is this one located elsewhere? Any thoughts ? I am thinking that this may not apply to my model, 87 LE Auto 4wd.
https://www.amazon.com/dp/B0789C7C8R/ref=cm_sw_r_cp_apa_fabc_48SGCYGJ31RK8W2B6QGR



I believe the part you want to fix the oil level light (yellow) is 89491-27020 (and potentially Gasket: 90430-27001, can't remember if it was included or not). That's what I used in my 87 LE Manual 4WD. It was an expensive part 6 years ago ($180) and it's probably NLA at this point, but there are a few sites that show it available, but your order will likely get cancelled if it's NLA.
https://toyotaparts.bochtoyotasouth.com/oem-parts/toyota-sensor-engine-oil-l-8949127020
https://www.megazip.net/zapchasti-dlya/toyota/sensor-engine-oil-level-8949127020
https://www.amayama.com/en/part/toyota/8949127020

Megazip and Amayama are international, but reputable sites. I've ordered from Megazip a few times (though only a couple orders actually shipped, due to NLA parts). I haven't ordered from Amayama yet, since PartSouq or Megazip usually have the part(s) I need cheaper.

[ssocal87]

Thanks everyone for your insight on this. I'll look around and see. It is pricey and the actual oil level is good, no leaks either. Again, in appreciation.

[originalkwyjibo]

If you just want the oil level light to stay off and are already diligently checking your oil, you can unplug the level sensor where it connects to the alternator harness and put a jumper wire into the chassis side of the harness. It's the small, white, two wire connector in the vicinity of the + box. You could also do this under the van at the sensor connection. One of my vans was setup like this when I got it. For those with the non-LE dual purpose warning light this may work to eliminate the oil level from the mystery of, "Why is my oil light on?"
Apply at your own risk.

[Temassi]

so I've got an '86 passenger van (not LE or DLX) and my oil light has been popping on after about 5 min after I start up. When I'm driving and get up to a decent speed it'll shut off. After slowing down it'll turn back on until I give it a little gas and that will shut the light off. I just replaced the oil pressure sender to eliminate that as a problem and the light is still coming on. Even if I leave the sender unplugged then start it up I'm getting the light after five minutes. My dipstick is showing full, so I'm a little at whits end on what it could be.

[timsrv]

Your van has an oil pressure switch (just below the oil filter) and an oil level sensor inside the oil pan. If low pressure or a low level is detected, the same light will come on (2 different ways to illuminate the same light). In my experience, the oil level sensor (in the oil pan) starts to fail at ~150k miles and causes intermittent false alarms. Every van I have ever owned has had this problem, so I'm betting that's your issue. I have tried to clean/repair these before to no avail.

You have already mostly troubleshooted your problem (we know it's not the oil pressure switch). The only things left would be an intermittent short in your wire harness (not likely) or the oil level sensor (likely). To troubleshoot, simply unplug that sensor (driver's side oil pan below alternator). If your oil light stays off, then that was the problem. Assuming that was it, here are your options:

1. Install an oil pressure gauge and ignore the light....be sure to check oil at regular intervals
2. leave the oil level sensor unplugged and check oil at regular intervals
3. pay ~$250 for a new sensor and it will likely last for the next 10 years (give or take).

In the past I've only done options #1 or 2, but for the van I'm driving now I decided to go with option #3. It's Toyota part number 89491-27020 (https://www.toyotapartsdeal.com/oem/toyota~sensor~engine~oil~level~89491-27020.html?vin=&make=Toyota&model=Van&year=1987&submodel=&extra1=&extra2=&filter=()). Toyotapartsdeal says $210, but then they cancel your order claiming it's NLA. According to my local dealer, MSRP is $339.04 but they discounted it to $250 (and they actually produced the part). The seal is Toyota #90430-27001 with an MSRP of $3.93 and a discounted price of $1.83. If you get the new sensor it should come with seal included (mine did). Tim

[Temassi]

Thanks for your response, Tim. I got under there and disconnected the level light and went for a drive. The light was on for the whole drive, never shut off. I had realized is still had my pressure sensor connected so wondered if that's what was throwing it off. Got home and disconnected the pressure sensor and the light was still on. Both were unplugged and still were giving the light.

However, after I connected them both back together and started her up the light stayed off. I took it for another drive and the light never came back on. I'm gonna keep my eye on it, but it seems to have maybe worked itself out? I'm not really sure.


edit: on a second drive the light turned back on. I may just pull the bulb and keep and close eye on oil level.

[timsrv]

Interesting. Sounds like you may have an intermittent short to ground in your wire harness??? I had a cargo van give me that issue once. I ended up running a new wire from the oil pressure switch up to the idiot light in the dash (yellow wire if I remember right). That solved the problem and it never came back. Of course doing that also bypassed the oil level sensor, but I keep a pretty close eye on oil level so I don't really need that one. Tim