Service warning light on only at high speed

[KayJay]

I don't know if there is more than one type of Switch with the Spade Terminal, but if you order one from a Guzzi place here (UK), they'll sell you an Adaptor Fitting as well, as the Threads are different (so the Switch won't screw into the Engine).
View attachment 22330

John, thanks to your research I was able to find several switches here in the US that looked to be an exact fit with the injector type connector. I had already ordered the spade type connector from MG Cycle and it should arrive tomorrow. I think the thread size will be correct without the adapter as I believe MG Cycle sells the smaller thread type for other model Guzzis. That said, I found a BMW switch that looks to be an exact replacement. I found these switches for as little as $5 online. I'll check with my mechanic tomorrow and see if he is willing to wait until I receive the BMW switch, or if he wants to go ahead and use the spade type switch along with the terminals you suggested. To confirm the threads are the correct size on the BMW switch I am going to order one and compare the switches. The BMW part number is:
BMW Engine Oil Pressure Sender Switch Oil Pressure Sensor #12 61 1 730 160
I'll let everyone know if the threads are correct. They sure look like they are. Hopefully any Stelvio owners who need to replace a switch in the future will be able to search this BMW part number and get an exact replacement switch without the headache of having to modify the wiring.

 

[KayJay]

Well,
I don't think the BMW switch will work. Everything was the same as the original except the overall size. Looks like i is a couple of millimeters larger so there may not be enough room. Will check and post the results.

 

[John Warner]

Both the ones I've fitted (to my 2009 & 2012 Stelvios) were a little longer than the originals.
The one I took off the 2012 was the later Spade Terminal type, with the 20+mm long Adaptor, so a slightly longer one will fit.
The Switch is oriented parallel to the left Cylinder, so even if it was much longer, it would just run alongside it.

 

[KayJay]

Both the ones I've fitted (to my 2009 & 2012 Stelvios) were a little longer than the originals.
The one I took off the 2012 was the later Spade Terminal type, with the 20+mm long Adaptor, so a slightly longer one will fit.
The Switch is oriented parallel to the left Cylinder, so even if it was much longer, it would just run alongside it.
View attachment 22371
View attachment 22372

Thanks John,
After taking a few measurements it Looks like the BMW switch I received today is exactly the same switch you used in your 2009 Stelvio. It wasn't the thread length, but the larger diameter that had me worried. At first sight I was concerned because the replacement switch diameter is 24 mm and the original was only 20 or 21mm. Knowing things are tight in there I wasn't sure I would have room to install it. Anyway, after checking, the specs match what you posted:
LENGTH ~ 41.25 mm

SPANNER SIZE ~ 24

THREAD ~ M12 x 1,5 mm

SWITCH POINT TO ~ 0.5 bar

SWITCH POINT FROM ~ 0.2 bar

THREAD LENGTH ~ 12 mm

It is brown. Looks like the exact same switch you used. I found them all over the internet here in the states.
BMW Engine Oil Pressure Sender Switch Oil Pressure Sensor #12 61 1 730 160

 

[John Warner]

Yep, identical to mine.
Seems to be fairly universal for most cars, and many Bikes.

 

[KayJay]

I just brought my bike home after having the oil pressure switch replaced and again the warning light came on at a steady RPM for more than 4-5 minutes and turned off immediately when throttle is reduced. The last time I checked, I got a dashboard error of DSB08. This time I'm getting a dashboard error of DSB07 with a brand new oil pressure switch. I have dozens of hours and crazy money into trying to solved this issue. At this point I have no idea where to turn. Mechanics here are still suggesting its a problem with the ECU, but I find that unlikely because the problem is so predictable. I can guarantee any time I run the bike between 3K and 4K RPM for more than 4-5 minutes, the warning/service light will come on. Does anybody have any idea what this could be?

 

[V700Steve]

Has anyone changed the upper pan gasket? Known to blow a piece out and cause low oil pressure. Not a sensor but mechanical.

 

[Raven]

Has anyone changed the upper pan gasket? Known to blow a piece out and cause low oil pressure. Not a sensor but mechanical.

I was thinking the same thing. I'm tackling that job on my Norge this weekend.

 

[KayJay]

Has anyone changed the upper pan gasket? Known to blow a piece out and cause low oil pressure. Not a sensor but mechanical.

Hmmm, The issue started immediately after I had the bike rollerized. At the time I asked the shop to flush the engine thoroughly so they most likely pulled the pan. The folks who just replaced the sensor checked the oil pressure and said it was fine, but now that I'm thinking about it they didn't leave the engine rpm at 3 -4K rpm for any amount of time. They checked pressure cold and continued checking until the engine was at operating temp. They then revved the engine several times to check throughout the rpm range but never let it stay at one rpm setting for any amount of time. i wonder if the pressure drops slightly after several minutes running at the same RPM due to a bad gasket? That said, rolling off the throttle (lowering oil pressure) turns the warning light off. Would the gasket still be a possible source of the problem under these conditions??

 

[Raven]

Depending on what flushing was done it could have caused a piece of the gasket to break loose. There is a pan gasket which they may have changed and then another gasket above it that is the culprit. They would not likely have replaced it.

 

[V700Steve]

Should be able to tell in parts for roller job on service ticket, gaskets.

 

[KayJay]

Should be able to tell in parts for roller job on service ticket, gaskets.

Thanks guys,
Doesn't look like the upper gasket was replaced so I guess I'll try that next. Do you still think the gasket is the problem considering the light goes out when the rpm is reduced and only comes on while holding a steady, unchanging rpm for several minutes??

 

[V700Steve]

Well, looks like you've done everything else. There is a better gasket than the thin black one that's original, a bit thicker and doesn't get brittle.

 

[KayJay]

Well, looks like you've done everything else. There is a better gasket than the thin black one that's original, a bit thicker and doesn't get brittle.

I suppose it is worth a try but I need to recover from the $1K spent trying to solve this issue without success. (in the dog house big time) As the oil pressure check showed the pressure to be within the proper range and considering I just changed the oil and filter, I may wait until the next oil change before dropping the sump myself. Looks like I will have to hone my mechanical skills if I'm going to keep this bike. it would be easier to sell it but I simply love this bike.

 

[Kevin.NZ]

Can you fit an oil pressure gauge onto the handle bars to monitor it yourself whilst driving?

 

[KayJay]

Can you fit an oil pressure gauge onto the handle bars to monitor it yourself whilst driving?

Thanks Kevin, I did see where others have done that. Thanks for reminding me.... Now to find an accessible place to connect to the lubrication circuit. Maybe at the oil cooler connection?
Still the one thing that makes no sense to me is the fact that the light goes out when I decrease rpm, in essence lowering the oil pressure....

 

[scottmastrocinque]

This is a shot in the dark, but there is a very real possibility that the non-OEM switch you used, has a different opening pressure than the stock OEM one. If this is the case, it may be that the switch is thinking that there isn't enough pressure when in fact there may very well be plenty.

The question is what the range for the OEM switch is. I see on your photo that the replacement switch you got is rated 0.2 - 0.5 bar which is 3 - 7psi.

The unusual circumstances about how the light goes out when you decrease RPM is exactly the same as I have encountered with the little fuel line between the fuel pump and fuel filter on my Piaggio scooter. It had suffered a crack which when idling, everything ran fine, up and including until about 15mph. After that speed/throttle position, the crack would open up and the pressure would drop.

If it is the upper pan gasket, then this may explain your phenomenon.

 

[john zibell]

Thanks Kevin, I did see where others have done that. Thanks for reminding me.... Now to find an accessible place to connect to the lubrication circuit. Maybe at the oil cooler connection?
Still the one thing that makes no sense to me is the fact that the light goes out when I decrease rpm, in essence lowering the oil pressure....

Lowering the RPM may just decrease pressure just enough that where oil is passing stops. Just replace that upper gasket and see what happens.

 

[John Warner]

. . . Now to find an accessible place to connect to the lubrication circuit. Maybe at the oil cooler connection? . . .

No good.
The Cooling Oil Circuit is completely separate from the Main Pressure Circuit (which supplies the Engine Main and Big-End Bearings).
Separate Pump (but in the same Housing as the Pressure Pump), takes Oil from the Sump, through a basic Strainer, then pumps it out through the Hose on the R/H side of the Crankcase, through the Cooler, and into the Heads, where it simply floods the areas around the Exhaust Valves.
No Pressure Sensor or Switch anywhere in that Circuit.

I'm with the others on replacing the Spacer Gasket.
Even if it's not the issue, it could save grief later.
The original is prone to failing, so you might as well pre-empt it.

 

[KayJay]

No good.
The Cooling Oil Circuit is completely separate from the Main Pressure Circuit (which supplies the Engine Main and Big-End Bearings).
Separate Pump (but in the same Housing as the Pressure Pump), takes Oil from the Sump, through a basic Strainer, then pumps it out through the Hose on the R/H side of the Crankcase, through the Cooler, and into the Heads, where it simply floods the areas around the Exhaust Valves.
No Pressure Sensor or Switch anywhere in that Circuit.

I'm with the others on replacing the Spacer Gasket.
Even if it's not the issue, it could save grief later.
The original is prone to failing, so you might as well pre-empt it.

Thank you all so very much! I pulled all the paperwork on the rollerization job and indeed only the lower gasket was replaced when the crankcase was flushed. It makes perfect sense that the upper gasket may have been compromised slightly during the process. I don't think the bike is in any imminent danger so I think I will wait until the next oil change to drop the sump.

I am very fortunate to have found this forum and everyone has been great. The level of expertise and knowledge shared is greatly appreciated.

Thanks again to everyone and I'll keep everyone posted on the results when I replace the gaskets.