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Discussion Starter #1
This is directed specifically for 2012+, but it probably covers previous models as well.

My new 2012 flickers the low oil pressure light at idle. The switch itself is opening and closing and doesn't appear to be a wiring issue. The manual states that the oil pressure specification is 28-85psi at 3,000rpm warm. Does anyone have a spec for idle pressure, or know the pressure that triggers the triggers the switch? I could not find either of those in the manual.

I am rigging up a mechanical gauge to check pressure out of the test port, and I was hoping someone would have a spec for idle pressure and switch trigger pressure. Once I get this tested, I am sure I will have more questions.

Thanks!
 

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Don't know specifically, but somewhere between 2 and 6 psi-- probably closer to 2; not much pressure or flow is required at idle.

I would suspect:

Bad switch
Water in the sensor boot causing a partial ground

I had a non-DL bikes oil filter clog up and it did the same thing (stator rubbed the magnets).
 

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Discussion Starter #4
I am suspecting bad sensor. If I had the idle pressure spec or switch open spec, it would easily confirm one way or another. Don't want to throw parts at it.

2psi? Wow, I would have never guessed that.
 

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I am suspecting bad sensor. If I had the idle pressure spec or switch open spec, it would easily confirm one way or another. Don't want to throw parts at it.

2psi? Wow, I would have never guessed that.
Most people freak out over low idle pressures which are generally pretty typical. I'd be more worried about seeing 85psi @ 3k as stated in the manual
 

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Discussion Starter #6
If the pressure is low enough to set the light, that indicates a problem. Whether that is a problem in the oiling system or just a bad sensor is yet to be determined.
 

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If the pressure is low enough to set the light, that indicates a problem. Whether that is a problem in the oiling system or just a bad sensor is yet to be determined.
True, and hopefully yours will be the latter. My statement was in regards to most who install an oil pressure gauge and see just how low the idle pressure is for the first time. Also, too high a pressure can be indicative of an obstruction downstream of the sensor which is often catastrophic due to low flow or misting
 

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I installed an oil pressure gauge on my '67 Triumph Bonneville and almost had a stroke:yikes: Oil pressure? What oil pressure?!
 

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With no issues like knocking noises or oil light on above idle there is almost no chance this is a low oil pressure problem. Almost certainly it will be a sensor. Quite common in fact. Many of these sensors are set to 5-10 psi and as long as that is met at low rpm then it will be fine at higher rpms. Thus the 28-85 psi in the manual. That's a pretty wide spread to cover their ass with. With the much better engine machining now loss of oil pressure through poor bearing fit is almost impossible. One of the good things of new technology!

If Suzuki installed an analog direct read oil pressure gauge on the V Stroms greywolf would have to make an "oil pressure" sticky! It would scare many owners how it would fluctuate!
 

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There is a big difference between engines with plain crankshaft and camshaft bearings and those with roller or ball bearings. The former need high pressure and the latter need low pressure.
 

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There is a big difference between engines with plain crankshaft and camshaft bearings and those with roller or ball bearings. The former need high pressure and the latter need low pressure.
That's what struck me with the high oem specs as I assumed the DL's ran all ball/needle bearings. I've seen other Vtwins become problematic as over zealous owners installed high pressure pumps creating to much misting in areas needing flow.
 

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The connecting rod to crankshaft bearings and the crankshaft to crankcase bearings are plain bearings. The camshafts run directly in the machined aluminum alloy of the cam tower. They need high pressure when running at high speed. The ball and needle bearings present in the engine can use small jets and splash oiling to get their oil right.
 

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Odd that the FSM does not specify idle oil pressure. The idiot light, however, is telling you that it is too low, and since the idiot light sensor wants to see something north of 4-6 psi (that's the normal range for this type of sensor) you must be pretty low.

I have installed a gauge and proper sending unit in my Vulcan which also came with just an idiot light. Not sure how applicable to the Wee this may be, but I'm showing about 20 psi at idle, at highway speed around 50-60.

Installing a real analog oil pressure gauge and sender is one of the easiest things you can do, and pretty inexpensive as well. The challenge is finding a place to mount the gauge. Or maybe fitting the sender as well because the gauge-type electrical sender is longer than the idiot light unit -- I haven't really looked at the placement of the OEM sender on the Wee. On the Vulcan it was no problem.
 

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Like the book says, 28psi is the lowest a pressure gauge should ever read. The light may go out with less than that. Still, the sender is the most likely culprit but it shouldn't be assumed to be the problem. It needs to be checked out.

Edit: My bad. The book value is for 3000rpm.
 

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The connecting rod to crankshaft bearings and the crankshaft to crankcase bearings are plain bearings. The camshafts run directly in the machined aluminum alloy of the cam tower. They need high pressure when running at high speed. The ball and needle bearings present in the engine can use small jets and splash oiling to get their oil right.
By golly and of course you are correct, the manuals in my mind seem to be overlapping and assumptions running wild
 

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Discussion Starter #16 (Edited)
That is 28psi minimum at 3000psi...the light should be a lot less than that to account for idle pressure.

For future reference to anyone searching this thread. This is running 15w40 conventional diesel oil. "Cold" ambient is 95 today, hot idle referenced to 4 bars on the gauge from idling, not driving:

Cold idle: 35psi
Cold 3000: 65psi
Hot idle: 15psi
Hot 3000: 55psi

Letting the engine continue to run until the cooling fans kick on:
Idle:10psi
3000: 35psi

Since I didn't drive it, letting it idle longer let the oil get up to temp. This should be the hottest the oil will see since we have an oil cooler (which also works as an oil warmer).

I wish I had enough time to test the new and old sensor and find the opening pressure of each, but I don't want the bike down that long. I'll rig a tester up tomorrow and find the opening pressure of the bad sensor for fun.

With these pressures, I am assuming the sensor is bad not knowing idle pressures. By all rights, if it is OK at 3000, it should be OK at idle, but mysteries sometimes occur.

If anyone now or in the future as a similar problem and would like to check their oil pressure, send me a message and I'll gladly ship you my gauge and setup. The gauge zip-ties to the crashbars allowing you to watch pressure as you drive, if you so desire. Not a permanent system, just for quick testing, needs nothing other than common hand tools to install and remove.
 

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Agree on the bad sensor. 10 psi at hottest idle should be well above the pressure number which activates the idiot light.
 

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Discussion Starter #18
Well, new sensor didn't fix it. Been riding my daily commute (14 miles) this whole time and haven't seen a single flicker. While diddling with the mechanical gauge, I changed the oil and filter as well and noticed no pressure difference with the old oil vs new. It was due for a change, so this is just fyi. I do not believe it is an issue with the oil itself or filter. This is the same combination I have run on my SV for years with success (as well as recommended on the forums).

I set off on a 6 hour road trip this week (my standard weekend 4 hour trip plus a pitstop) thinking it was fixed and I was ready to go. With her all loaded up, bungees and ratchet straps everywhere, I made it 2 hours into the trip. This is all high speed interstate stuff, and the light started to flicker at highway speed and rpm. When I first seen it was a construction zone where speeds dipped down and I was running 4k in 6th. After the 2 hour interstate run, it was all backroads from there. I was quite unhappy this problem resurfaced so far from home (to put it mildly) and decided to just continue on, which I did. :headbang:

Light is random. I have never seen the light above 4500rpm. It always goes out. Once it is hot and starts to light, most of the time it lights at idle, but sometimes not. Sometimes a quick change of direction, braking, acceleration, or turning will cause it to flicker. Shutting the bike off for a couple hours, letting it cool, "resets" the light and it stays off until it is hot again. A typical gas station stop is not long enough.

It only does it when the engine is blazing hot. My 14 mile commute (and just idling like before) just won't do it, it seems, needs long distances.

No abnormal engine noises. This bike has a lot of weird noises my SV doesn't, but I think that is due to the full exhaust on the SV is so loud I just can't hear anything. Definitely no rod knock or severe timing chain slap that I was expect to hear if the oil was truly low on pressure at a decent rpm/throttle. I say severe slap because I do think I hear a little based on experience with other engines (old v8's), but I could be mistaken.

I've got close to 300 miles this weekend on it with it flashing the light. I am a little over halfway through my trip and in no place to do any diagnostics. I hope to get this fixed once and for all when I get back. I see 2 possible causes right now, pulling this completely from my anterior regions.

1. I do actually have a momentary loss in oil pressure. If this were to happen, it would make the most sense for it to happen at a hot oil temp when pressure is naturally lower, like it does. A short term loss (let's say a couple second or less) in oil pressure wouldn't necessarily cause it to audibly knock immediately, but engine damage is occurring. However, I have no idea what would actually cause this momentary and somewhat random loss in oil pressure.

2. Wiring short. The way it appears to me is that the pressure switch turns the connection to ground on and off. With the switch closed (no oil pressure), a connection to ground is established and the light lights. Switch opens, no connection to ground, no light. However, since the ECM lights this light for a FI fault, there must be multiple connections to ground. Possibly the wiring is chafed or some other fault that has occasional connections to ground, just like it went through the switch, lighting the light.

My problem with this theory is why only hot and why only below 4500rpm. If I rev the engine above 4500, the light always goes out. Doesn't make a lot of sense to me why a consistent 4500 rpm or above would shake a wire in a way to make it stop shorting.

Remember that I tested the old sensor with the engine running and the light flickering. The switch was switching from near infinite resistance to just a couple ohms. However, IIRC I checked this with the wiring still attached. If there was a direct short in the wiring, I would also have gotten these readings.

Scratching for any and all opinions here. I am not convinced that it is actually losing oil pressure and I still have a hunch that it is a wiring/electronically glitch, but I have no proof of that. The strom is my main mode of transportation, and losing oil pressure is a serious matter, so this is greatly concerning to me. I do not want to have to pull the engine in a 2012 glee anytime soon.
 

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A partial, intermittent short to ground, or to another wire in a harness somewhere is consistent with what you describe. Try running a new wire from the sensor and splicing as close as you can to the ecu (I assume the ecu triggers the light). There are reports of chafing where the main harness goes over a frame crossmember.
 

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Discussion Starter #20
Didn't realize there was a common issue there. Quick google search of vstrom wire chaffing has landed me more results than what I cared to see. Found one thread of a chaffed wire causing an oil pressure light. Looks like I found a direction. Seems the chaffing will eventually shut it down when enough wires get shorted. Yay.

I just hope I don't need a new harness like I see in those discussions. Mine is now well out of warranty.
 
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