I have a 2011 x5 that when it gets up to speed, the limp mode/engine malfunction warning comes up, but there is no change in how it runs before or after. If you turn the car off and then back on, the warning is gone until you drive it some more. If you drive it in manual mode it never throws the warning. Any ideas?
You say no code, but what scanner are you using? even if the check engine light clears itself, you should have a historical code.
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There was a P112F historical code.
Which engine? N55?
The code says there's a mismatch between measured throttle angle and the intake manifold pressure.
Usually this would mean there's an error in one of the signals. Either the throttle angle sensor (of which there are usually two ink parallel for redundancy or the map sensor).
What scanning capability do you have? You need to see those sensor values realtime preferably on a graph to see if there are impossible (bmw will call improbable) values. Eg instantaneous changes that typically happen from intermittent opens or shorts but are obvious for example an instantaneous change in pressure or throttle angle.
TPS sensor failure will give tries symptom but you need to see what the readings are. Also; n55 along with most bmw motors don't use the throttle for throttle they change the intake valve lift instead the throttle plate is used for start/idle and limp home I'm guessing.
It’s an N55. I don’t have the coding capability to record these real time values unfortunately. Hate to throw parts at the problem but these two sensors are at least inexpensive enough to replace one to see the impact.
But does the fact that the malfunction warning goes away after stop/start, or that it doesn’t appear when in manual mode lead one way or the other?
Some sensor values are available with phone apps. That said, get a foxwell scanner it will pay for itself quickly.
When you way manual mode are you saying you are making all the shifts or just sport mode where the car makes the shifts but in sport mode : DS?
Last edited by andrewwynn; 05-01-2023 at 11:38 AM.
Manual mode = when I’m making all shifts
So that suggests you shift easier than the program. Try shifting at lower rpm to lug the engine a bit to reproduce the error.
I will do some more tests and see if I can find a mobile app that will record these values. Thanks!
I will do some tests and see if I can find a mobile app that will record these values.
I haven’t been able to capture the values when the error is thrown. I WAS able to reproduce this two times though. Once on the highway, another time going up a very steep hill. But I can’t do it in command. I even tried putting it in 8th gear in manual mode and stepping on it, but nothing.
I can get it to throw the warning by lugging the engine (coasting to slow down a bit, then flooring it) but no code is thrown and the warning disappears when the car is turned off/on.
P code? Do you not have BMW capable scanner? Code should be hex. No history cider even?
Does MIL light blink or half engine?
"Feels like" low fuel pressure.
These are graphs of mine vs. my buddy who was having the same problem. His car was not maintaining correct fuel pressure. It should be constant and in my case 101.5 psi. It didn't change even a little no matter the throttle position. Turned out to be the fuel pump. It was a bit of a gamble because it could have been the fuel pump controller.
Last edited by andrewwynn; 05-12-2023 at 10:58 AM.
I don’t have a proper scanner but the mobile app I have should let me see real-time fuel pressure values. No, the MIL does not blink, the car runs absolutely normally, and the MIL goes away after you shut the car off.
I’m not able to get any further on this. Any suggestions? It comes on consistently when the engine is bogged down and you try to accelerate.
You need diagnostic that will help you eg foxwell 720 scanner you can read real-time values like fuel pressure like shown above. My buddy with 535 from the picture had an end of life fuel pump causing nearly identical symptoms but I wouldn't use a parts cannon. Get the tools you need to work on your car.
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