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post #11 of 13 Old 17th June 2019, 07:45 PM
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How long can you run without the MAF's and not cause any harm to anything?

Mine has been experiencing very slight losses of power, but it's more like when I stomp on it, the power I expect isn't there, it's lessened. When I feel the power the way it should be in that band, it's nuts, so there are definitely many times when I demand the power and it's just not there the way it should be. No codes related to anything MAF or otherwise right now.

97K miles, unsure if MAF's have ever been changed and that goes for the CPSs and TPSs too. But as noted, not getting any codes, and I would expect a code if it was related to one of these electrical components.

New (old): 2003 E39 M5 TiAG
Old: 2001 E46 330i Steel-Grey Metallic (Totalled)
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post #12 of 13 Old 18th June 2019, 01:34 AM
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Lack of power intermittently sounds like CPS need replacing. If you have original CPS they can be almost dead before they throw a code.
To your question you can run with the MAFs unplugged forever as long as you pay attention that the DME does not get an air temp from the MAFS anymore.
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post #13 of 13 Old 4th July 2019, 12:45 PM Thread Starter
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To finish this off :

After almost 3 weeks I picked my car up yesterday and ragged the nuts off it !!! All seems good although at one point in traffic the temperature gauges started to creep past mid point, I'll have to keep an eye on that although I did have a new water pump fitted about 2-3 years back...

Anyway to round off, my Indy struggled with this as the only codes he could find were the same as I'd got along with a fuel pump code. So he changed the fuel pump and nothing improved.. so he took the fuel pump off and fitted it to another car and it worked fine on that...

MAFs I'd changed with Bosch ones from Germany with the correct serial numbers for our cars.

Front O2 sensors had been replaced last year so he doubted it was those.

Having cleared the codes initially he struggled to find any more information so it was a case of guess work as the car was now only starting and then almost immediately stalling.

Symptoms really didn't appear to tie in with bad CPS as I've experienced those in the past and would have picked up on it way back.

Anyway we had a really good chat about what I'd experienced and how it felt etc and we went through various ideas, such as plugs, coils, injectors, vacuum leak, vanos solenoids and so on...and one by one we discounted them, the bottom line was that it felt like fuel starvation but originally only under certain conditions which were usually when pressing on hard, overtaking and leaning on the throttle heavily.

So back to the fuel supply and a close look at the fuel filter and wallah, we found upon close inspection it was partially blocked and restricting fuel to the pump which had been working overtime and we think was intermittently curling up and almost dying.

In summary - after a new fuel pump, fuel filter, fuel tank sensor and a pressure valve have been fitted warp speed is back on tap...

Sadly though the total bill came to £2.70 less than a 2003 C200 Kompressor with 90k miles on the clock cost me to buy to run around in whilst my M was off the road...
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Why is the slowest person always at the front of the queue ???

Last edited by SeeSure; 4th July 2019 at 12:53 PM.
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