TBM Oil pressure warning and engine cut out

Before I raise a bug for this, I wanted to check if it is actually pilot error!

Relatively frequently (maybe once or twice in a 4 hour flight) in the TBM I get an oil pressure warning and the engine cuts out.

I am able to restart the engine by switching the ignition toggle to on and pushing the engine start switch to on. When that switch toggles back I can switch ignition back to auto. At this point, after 10-15 seconds the engine restarts and the oil pressure warning disappears and all returns to normal.

Just to confirm, I’ve searched the forums and there are a couple of similar issues mentioned in some threads but these were resolved by fixing lack of fuel (usually through switching the fuel selection to auto). I can confirm I have the fuel selection set to auto. I also get this issue seemingly regardless of fuel levels.

I suspect this is something I’m doing wrong. I try to make sure that torque stays out of the red and I throttle back to ensure ITT temp stays in the green.

Any suggestions or help appreciated.

Thanks in advance

First of all I would suggest you’re running out of fuel, but in that case you never could start the engine again. I never faced this problem except once with empty fueltank ( 10 Gal rest) My longest flight with the TBM were around 3.30h
So I guess you have any key or some button mistakenly assigned to fuel cutoff because I don’t think it’s a bug.

The thing with Oil pressure came shortly after engine stop, so it’s not a symptom but a result of fuel cutoff and engine stop.

Did you switch on some failure in the options? Maybe could be a reason too.

I wonder too if you have changed the failure options in anyway?

I have 40 hours in the TBM with unlimited fuel set to on. Nothing has ever happened to me so far. I always have the throttle set to around 85% at cruising height.

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Thanks for that. I will check key bindings and double check the fuel position. Weird thing is that I can restart the engine which would suggest the fuel cut off is only temporary.

I will check failures too, thanks

Sorry, duh… I didn’t read who posted the question. My bad, Dude.

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Ok, so checked the failures - definitely don’t have these set on. Also checked all my contorl bindings. I’ve realised that I’ve had the mixture setting linked to one of the levers on my throttle quadrant - obviously the TBM doesn’t have a mixture control, but I wonder if that is the cause of the problem. Honestly not sure if I might have moved that control during the flight that causes the mixture to go to zero which, on a Cessna, would cut the engine? Don’t know but I will try that and see if the problem goes away.

Thanks for your help all.

Ok, than you found a small Bug :sunglasses:
And yes, when you move the mixture to the very end you will cutoff the engine and as far as I correctly remember is it so in real life too.

OK, so experimented with this a bit and now understand what is going on.

Can anyone confirm for me that there is no mixture control on the TBM?

The issue arises when I have a throttle quadrant axis mapped to the mixture control, even though the TBM has no mixture control as far as I know.

If this mixture control is moved to below 50%, the engine cuts out. It can then be restarted, even if the mixture control is left where it is, i.e. below 50%. If the control is moved AT ALL when below 50%, the engine cuts out (for clarity, that is moving the control up or down). Again, regardless of where the control is, the engine can be restarted. So, for example, moving the control from 60% to zero will cut the engine. After restarting, moving the control from zero to 100% will still cut the engine. It seems tied to moving the control at all when below 50%. Moving the control from 60% to 100% does nothing. Moving the control from 100% to 60% does nothing.

Obviosuly the fix is easy - unmap the mixture control! However, I will zendesk anyway.

I think the culprit for my engine failures is then my cat :cat: He likes to rub his cheeks on the quadrant levers…and if he does that on the mixture control, the engine cuts out :crazy_face:

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:rofl: evil :kissing_cat:

You’re totally right, the TBM does not have a Pilot mixture control. Anyway, the FADEC must reduce the fuel injection level during climb. But it’s automatic like a jet engine. So you found the backdoor to the programming of TBMs FADEC. :crazy_face:

That’s because it is, you know, a jet engine :smiley:

Yeah, you’re right, actually it is a jet engine. :innocent:

Thanks - I had to google FADEC! Mixture ON/OFF toggle is definitely Digital though!

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I had this happen. I was using my default throttle config with both mixture and prop rpm controls. I just left them at the maximum setting and didn’t use them.

Turns out the slightest - and I mean SLIGHTEST - movement of either of those will cause the engine to shut down. This also occurred for me in the Citation. I suspect it could also have an effect in other planes that don’t use mixture and prop controls.

What I ended up doing was saving out a separate controller config for my throttle where those 2 unneeded options are disabled. I switch throttle control layouts based on what plane I’m flying.

I haven’t had the problem since.

EDIT
I discovered what the issue was, but won’t take credit for the solution. Someone else had recommended I save out a separate config for my throttle. Sounded like a hassle at the time, but turns out it was dead simple and only takes a few seconds to switch when I switch aircraft.

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Hi All!
I have this same problem in the 930 but I checked all my bindings and they are all fine. I also turned on auto mixture and unlimited fuel and this did nothing. Shortly after takeoff, I notice the oil pressure begins to drop to 1, and then the engine proceeds to cut off. The only fix I have found to this is placing the AI in charge of the airplane when I first notice a pressure drop as they normally can correct it. If anyone has any ideas on how to fix this I would be very grateful. Thanks.

Just set any mixture control you have to 100% and don’t touch it afterwards… The TBM doesn’t have pilot controlled mixture.

I do not have a mixture or prop control only throttle

I just flew in a Bonanza and had the same problem occur

@caucasianmamba2

The post right above your first. That’s the solution.

The mixture is likely bound somewhere and being set to 0 causing the issue. That’s the only thing that would affect both the TBM and Bonanza.

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This reminds me of the time I didn’t notice that elevator trim was also mapped to my rudder peddles. It made taking off incredibly difficult.