running out of get up and go.

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Mark Piercy said:
Checked mine yesterday and it's been running around with the pipe off.. I didn't even feel the difference.
Click to expand...
On EGR versions of the M51 with a MAF, as long as the MAP sensor is electrically OK having the pipe off makes no difference on either of mine, pre EGR it does affect running if the pipe is off.
 
Datatek said:
On EGR versions of the M51 with a MAF, as long as the MAP sensor is electrically OK having the pipe off makes no difference on either of mine, pre EGR it does affect running if the pipe is off.
Click to expand...

That is not possible on either engine. The ECM gets it's manifold pressure info from the MAP sensor and adjusts fuelling subject to boost pressure. If the pipe is disconnected or the MAP sensor fails it is not possible for the engine to produce it's normal power. Power has to be reduced.
 
wammers said:
That is not possible on either engine. The ECM gets it's manifold pressure info from the MAP sensor and adjusts fuelling subject to boost pressure. If the pipe is disconnected or the MAP sensor fails it is not possible for the engine to produce it's normal power. Power has to be reduced.
Click to expand...
Sorry, but we now have 3 cars that function normally with the MAP pipe disconnected. Electrical disconnection does indeed result in reduced power. I assume that the MAF provides the necessary information. On pre EGR/MAF engines, disconnecting the MAP pipe does result in reduced power.
 
Datatek said:
Sorry, but we now have 3 cars that function normally with the MAP pipe disconnected. Electrical disconnection does indeed result in reduced power. I assume that the MAF provides the necessary information. On pre EGR/MAF engines, disconnecting the MAP pipe does result in reduced power.
Click to expand...

MAF as explained many times has nothing at all to do with fuelling. It is not possible that the engine runs normally with no pipe to MAP sensor.
 
wammers said:
MAF as explained many times has nothing at all to do with fuelling. It is not possible that the engine runs normally with no pipe to MAP sensor.
Click to expand...
So we are making the impossible possible. The MAF has no effect on fuelling except when it doesn't work and then as you say "the ECU goes crazy".
I believe what I see with my own eyes.
 
Datatek said:
So we are making the impossible possible. The MAF has no effect on fuelling except when it doesn't work and then as you say "the ECU goes crazy".
I believe what I see with my own eyes.
Click to expand...

The only parameter from the MAF sensor that has anything to do with fuel is the air temp, used in conjunction with fuel temp readings from fuel temp sensor and engine temp sensor used by the ECM to minutely adjust fuel mass. Air flow through the MAF has no influence whatsoever on injected fuel quantity.
 
D1428FB3-8866-483B-8124-F6E617B961E1.gif
 
Both BMW and LR passed the buck to Bosch for them to patch up the fuelling software issues. I think was always a ‘that’ll do scenario’ from start. people get concerned when they see the software version with their nanocom (DDE 2.1/2.2 late) when they think their p38 should be early due to MY (your P38D will not run if you set to early)
They bodged it IMO

I prefer having an IAT

Only experience I have is I forgot to plug either pipe or think it was the connector into my MAP when I did my temp sensors and snapped a glower - it seemed major as I struggled to pull off or change up gear without stalling, hardly had enough power to pull around it’s own weight.
 
Datatek said:
On EGR versions of the M51 with a MAF, as long as the MAP sensor is electrically OK having the pipe off makes no difference on either of mine, pre EGR it does affect running if the pipe is off.
Click to expand...
I have ran it before with the map unplugged as I had a noise from the FIP, it turned out the intank wasn't supplying enough file and the FIP was trying to compensate for it?? The sound went when the pump was replaced. But I can confirm that it'll run with both the MAF and map unplugged as I have tried this before to rule out the issue at the time.. I did however notice a small drop in power and a rise in the MPG but it could be driven quite happily and with ignorance if not known about... And.... Not lamp on the dash for any of the above...:)
 
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