Air Flow Meter

Heliospherez

Heliospherez

Heliospherez

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What damage would removing the Air flow meter cause on a BMW 330D, as I think this may have been faulty.

Is it really needed ? I have already taken the unit off, and the motor is still running perfectly - in fact - better than it was before ?

Is it just used to check the amount of air entering the engine?
 
Last time i checked, it was pretty important as it lets the ECU know how much air is coming into the engine. Or am I getting confused again?
 
im sure BMW put it there for a reason... would be a bit of a waste if it wasnt. It does measure the air and prepares the fuel for the mixture i would have thought... therefore you could be running rich/lean without. Thats a guess...personally i wouldnt remove it.
 
I know on my Primera (different engine, different fuel) it does exactly that, measure the mass of the air thats coming in, and gets the appropriate ammount of fuel, tbh i'm surprised your engine runs with out it being connected.

I'd connect it back up ASAP. If somethings wrong, take it to a garage.
 
I have already disconnected the unit, and the engine now runs substantially better.

Before, with *** meter connected, the engine would stall, hesitate and had black smoke belching from the exhaust. I also had a dead spot at approx 1500 RPM - Fairly sure the Air Flow Meter is a dud......



Car needs a new one - and i have been quoted £258 from the dealer.....
 
Easy enough to find second hand. Mine went on my old 325 and the part was 200+vat new. Found one on ebay for £25. Jobs a goodun!

It will run on a default setting without it connected, unfortunatly this cant adjust fueling for different densities in air so it will run leaner in colder air, richer in warmer air.
 
R220 said:
im sure BMW put it there for a reason... would be a bit of a waste if it wasnt.
Click to expand...

Well they put indicators on... :p

The car is probably now in "limp home mode" and using other sensors to guestimate how much fuel to inject. The airflow meter was probably giving too high a reading so it was dumping a lot of extra fuel in. Can you get one from a scrappy? The car does need it!
 
If your car runs better without it then it would indicate that the air flow meter is knackered, I had the same problem on my Golf.
 
Surely without the air flow meter its going to think there's little air flow and run pretty learn... so it will feel better, but your fuel economy will die with the airflow meter and you could do some damage to the motor. Shouldn't be too much for a replacement.

Well, I think I'm right.
 
divosuk said:
I have already disconnected the unit, and the engine now runs substantially better.

Before, with *** meter connected, the engine would stall, hesitate and had black smoke belching from the exhaust. I also had a dead spot at approx 1500 RPM - Fairly sure the Air Flow Meter is a dud......



Car needs a new one - and i have been quoted £258 from the dealer.....
Click to expand...


Thats less than I thought it would be. :)
Is it a flap one or a wire one?
 
Guys, it's a diesel so the concept of rich and lean has little meaning.

The airflow meters on diesels are primarily part of the emmisions control system to ensure that too much fuel is never injected which causes (more!) black smoke. Diesels will almost always run with it disconnected, and in fact is a fairly sure way of telling if it's duff.

Without the AFM the car may be running better, but it won't be optimal.
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=230028073258
 
Most cars will run with no MAF. They will just revert back to mapped settings in the ECU. It's only a 'get you home' feature more than anything so I would replace the MAF as soon as you can.
 
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