Fitting an oil gauge sender to a 2GR-FE

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Re: Fitting an oil gauge sender to a 2GR-FE

Post by shinny » 17/06/18 21:49

gavsdavs wrote:
15/06/18 20:34
I've never had a car with an oil pressure gauge. What's it read in, PSI or Bar ? What's a normal value ? Does pressure vary with engine load/RPM ? I'm all for knowing what's going on - it just wouldn't be my first choice of monitoring as I've never suffered an oil pressure related issue.
PSI or Bar, your choice.

Mine is in Bar, so that's what I'll I'll talk in. When hot, my engine reports about 1bar pressure for every 500rpm, maxing out at 7bar (there's a pressure relief valve set there within the engine). When cold the pressure will be higher, but still maxing at 7bar.




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Re: Fitting an oil gauge sender to a 2GR-FE

Post by Lemuts » 18/06/18 14:22

OK at the risk of a flame breaking out and almost certainly teaching you all to suck eggs…………

As I see it oil pressure is a very important factor in ensuring the longevity of my engine.

Oil pressure is higher when the engine is cold due to the increased viscosity of the oil, and also increases with engine speed until the relief valve in the oil pump opens to divert excess flow. Oil pressure is lowest under hot idling conditions, and the minimum pressure allowed by the manufacturer's tolerances is usually given at this point. Excessive oil pressure may indicate a blocked filter, blocked oil gallery or the wrong grade of oil. Low oil pressure indicates worn bearings or a broken oil pump. In the case of the 2GR engine, at idle the oil pressure is 11.6 psi or more and at 6,000 rpm 55.5psi or more.

I just can’t see how it is possible to monitor the variances in pressure that are known to take place with a simple on/off light. :drive1:

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Re: Fitting an oil gauge sender to a 2GR-FE

Post by gavsdavs » 18/06/18 22:31

Lemuts wrote:
18/06/18 14:22
OK at the risk of a flame breaking out and almost certainly teaching you all to suck eggs…………

As I see it oil pressure is a very important factor in ensuring the longevity of my engine.

Oil pressure is higher when the engine is cold due to the increased viscosity of the oil, and also increases with engine speed until the relief valve in the oil pump opens to divert excess flow. Oil pressure is lowest under hot idling conditions, and the minimum pressure allowed by the manufacturer's tolerances is usually given at this point. Excessive oil pressure may indicate a blocked filter, blocked oil gallery or the wrong grade of oil. Low oil pressure indicates worn bearings or a broken oil pump. In the case of the 2GR engine, at idle the oil pressure is 11.6 psi or more and at 6,000 rpm 55.5psi or more.

I just can’t see how it is possible to monitor the variances in pressure that are known to take place with a simple on/off light. :drive1:
Excellent stuff, I don't think they expose this in the ECU OBD data - Shame

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Re: Fitting an oil gauge sender to a 2GR-FE

Post by shinny » 19/06/18 0:39

gavsdavs wrote:
18/06/18 22:31
Excellent stuff, I don't think they expose this in the ECU OBD data - Shame
No, because the ECU probably doesn't know it. Certainly on the 3s engines, the oil warning light is done on a pressure switch and there's no sensor even connected to the ECU, let alone feeding it anything more sophisticated than a binary OK or bad.

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Re: Fitting an oil gauge sender to a 2GR-FE

Post by gavsdavs » 19/06/18 9:08

shinny wrote:
19/06/18 0:39
gavsdavs wrote:
18/06/18 22:31
Excellent stuff, I don't think they expose this in the ECU OBD data - Shame
No, because the ECU probably doesn't know it. Certainly on the 3s engines, the oil warning light is done on a pressure switch and there's no sensor even connected to the ECU, let alone feeding it anything more sophisticated than a binary OK or bad.
2GRs have a lot of sensors on them - it's a lot more modern than a 3S :)


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Re: Fitting an oil gauge sender to a 2GR-FE

Post by Lemuts » 19/06/18 9:39

Sorry guys missed the obvious - attached shows the existing oil pressure switch and the plug we used for the pressure sender.
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Re: Fitting an oil gauge sender to a 2GR-FE

Post by jimi » 19/06/18 10:49

gavsdavs wrote:
19/06/18 9:08

2GRs have a lot of sensors on them - it's a lot more modern than a 3S :)
Still doesn't have an oil pressure sensor, only a pressure switch ;)
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Re: Fitting an oil gauge sender to a 2GR-FE

Post by shinny » 19/06/18 11:45

Lemuts wrote:
19/06/18 9:39
Sorry guys missed the obvious - attached shows the existing oil pressure switch and the plug we used for the pressure sender.
Looks like a similar location to these available on the gen3 3s engines:

Image

Great way to fit a sensor IMHO.

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Re: Fitting an oil gauge sender to a 2GR-FE

Post by gavsdavs » 19/06/18 18:46

jimi wrote:
19/06/18 10:49
gavsdavs wrote:
19/06/18 9:08

2GRs have a lot of sensors on them - it's a lot more modern than a 3S :)
Still doesn't have an oil pressure sensor, only a pressure switch ;)
You'd think for a few extra quid they'd bung a real sensor in there :(

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Re: Fitting an oil gauge sender to a 2GR-FE

Post by shinny » 19/06/18 20:26

gavsdavs wrote:
19/06/18 18:46
jimi wrote:
19/06/18 10:49
gavsdavs wrote:
19/06/18 9:08

2GRs have a lot of sensors on them - it's a lot more modern than a 3S :)
Still doesn't have an oil pressure sensor, only a pressure switch ;)
You'd think for a few extra quid they'd bung a real sensor in there :(
Why? What would they use it for?

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Re: Fitting an oil gauge sender to a 2GR-FE

Post by gavsdavs » 20/06/18 8:09

shinny wrote:
19/06/18 20:26
gavsdavs wrote:
19/06/18 18:46
jimi wrote:
19/06/18 10:49

Still doesn't have an oil pressure sensor, only a pressure switch ;)
You'd think for a few extra quid they'd bung a real sensor in there :(
Why? What would they use it for?
I'm confused and I'm finding your comments a bit contradictory. Earlier in the thread you were espousing how valuable a real oil pressure gauge was, which is best supported by a sensor for progressive data rather than simply a switch of binary output. Now you're questioning why they might have wanted to fit a sensor instead of switch ?

Like many other things on the engine, to feed it into the ECU for monitoring/safety purposes.

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Re: Fitting an oil gauge sender to a 2GR-FE

Post by TonyleFrog » 20/06/18 10:12

gavsdavs wrote:
15/06/18 20:34
I've never had a car with an oil pressure gauge. What's it read in, PSI or Bar ?
Depends on the gauge: can be either. The majority of aftermarket ones are in bar.
Unless it's a US made item (they don't understand non-imperial based units)
Some UK gauges (e.g. Smiths classic type) are also in lbs/sq. in.

Just to try and confuse you, Defis are calibrated in x100kPa (kiloPascals).
Image
100kPa is equivalent to 1 bar - https://www.convertunits.com/from/kPa/to/bar
gavsdavs wrote:
15/06/18 20:34
What's a normal value ?
Depends on the engine and also whether it's cold or hot.
gavsdavs wrote:
15/06/18 20:34
Does pressure vary with engine load/RPM ?
Yes. Again it depends on the engine. Some drop more than others when idling.
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Re: Fitting an oil gauge sender to a 2GR-FE

Post by shinny » 20/06/18 15:28

gavsdavs wrote:
20/06/18 8:09
shinny wrote:
19/06/18 20:26
gavsdavs wrote:
19/06/18 18:46


You'd think for a few extra quid they'd bung a real sensor in there :(
Why? What would they use it for?
I'm confused and I'm finding your comments a bit contradictory. Earlier in the thread you were espousing how valuable a real oil pressure gauge was, which is best supported by a sensor for progressive data rather than simply a switch of binary output. Now you're questioning why they might have wanted to fit a sensor instead of switch ?

Like many other things on the engine, to feed it into the ECU for monitoring/safety purposes.
It's all to do with use case:

1) A car manufacturer is looking for simple, reliable and cheap. Your average driver only cares about warning of a catastrophic failure, in which case a simple switch set at a suitably low point so it doesn't give false negatives is ideal. Provided the oil system is working, what does the ECU care about oil pressure? A really sophisticated ECU could use it to determine oil service intervals I guess... but a worn, high mileage engine or the wrong oil grade would screw that up. There are some rather unusual errors that could be caught (eg. failed pressure relief valve) but that doesn't justify the expense over thousands upon thousands of vehicles.

2) An enthusiast, modder or racer really cares about the details and health of their engine. They are prepared to learn what their engine does, to put up with false positives and may well need to know what's going on as they modify the engine or oil system. For example, the warning I set on my Defis means that I get a warning if I accidentally let my revs drop to 600rpm (ie. nearly stall) when maneuvering. That's unacceptable for mass market, but it just fine for an enthusiast to understand and ignore.

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Re: Fitting an oil gauge sender to a 2GR-FE

Post by gavsdavs » 20/06/18 17:29

shinny wrote:
20/06/18 15:28
It's all to do with use case:

1) A car manufacturer is looking for simple, reliable and cheap. Your average driver only cares about warning of a catastrophic failure, in which case a simple switch set at a suitably low point so it doesn't give false negatives is ideal. Provided the oil system is working, what does the ECU care about oil pressure? A really sophisticated ECU could use it to determine oil service intervals I guess... but a worn, high mileage engine or the wrong oil grade would screw that up. There are some rather unusual errors that could be caught (eg. failed pressure relief valve) but that doesn't justify the expense over thousands upon thousands of vehicles.

2) An enthusiast, modder or racer really cares about the details and health of their engine. They are prepared to learn what their engine does, to put up with false positives and may well need to know what's going on as they modify the engine or oil system. For example, the warning I set on my Defis means that I get a warning if I accidentally let my revs drop to 600rpm (ie. nearly stall) when maneuvering. That's unacceptable for mass market, but it just fine for an enthusiast to understand and ignore.
Do you think the cost of a sensor (compared to a simple switch) is significant in the larger picture of an entire engine ? (I don't know, I'm just asking). It just sounded like you thought you'd 'saved' your engine by knowing its oil pressure was low and that having a sensor (instead of a switch) was a key differentiator there.

More modern ECUs are quite good at putting the engine into 'running but limited' safe modes in the event they see conditions that might be damaging. I'm not suggesting showing this to the standard 'doesn't care about engine innards' driver, but the ECU might be able to use a continual low pressure warning to chuck a code or illuminate warning LED a bit earlier.

Is the cost difference significant ? Can they be installed in the same place ?

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