engine wont rev past 3000rpm unless its not moving

braddy2610 said:
AnttiO said:
Inpa or ista rheingold would be best for diagnosting.
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Just found the ambient temperature is different to my air intake temperature by 30℉ so I guess it's the maf
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Just a thought... It may be the MAF, but...

1. The MAF doesn't measure temperature, but the density of air by running it past a sensitively controlled heating element effectively. The IAT (Intake air temp), a simple thermistor is what i think you're thinking.

2. The temperature of the intake will always be higher than ambient, because the heat-soak from the engine will heat the air on its way in.

3. The ECU will not throw an EML or problem for a 30F disparity in temperature between Intake and Ambient.
 
Ok well. I'm stuck then it's still running lean won't drive under load don't want to change maf if it's not that what should my air mass. Be at idle it's says 3.0 g/sec air pressure 33kpa gas pressure 451 kpa
 
Do you have INPA? It would be great to see some screenshots of livedata readings at idle. I can then compare those for my own car.
 
My INPA reading last week (warm engine) was:

Air pressure 34
Gas pressure 453
Air mass 13kg/h

If you're air mass really was only 3g/sec, that is 10.8kg/h. So yours is a bit lower than mine. Don't suppose your air filter or air supply in general is blocked in any way??
 
The only other thing you might want to look at, and is something I have seen on another car I had, is the camshaft sensor. It can stop the car from revving when in gear, and doesn't always throw a fault light. You should get a fault code through INPA, but not always.
 
what about the Vanos o-rings, just a thought.

Problems normally experienced:
Loss of power and torque below 3,000 RPM and or when the A/C is turned on.
Possible engine bogging down and then surging to 3,000 RPM.
Engine hesitation and uneven power throughout the RPM range under 3,000 RPM.
MPG decreased, and vehicle takeoffs are difficult.
Louder than normal idles and engine misses.
 
well that was a waste of money brand new maf same problem going to take it to the local garage see if they can get to the bottom of it grrr :x
 
have you got any bmw software ie DIS v57 or INPA?

if you have DIS v57 you could try full test and the clear all errors so if that works.
 
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