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Discussion Starter #1
Hi all,
Had to replace my MAF sensor after my old one was flat spotting alot. Had the ECU re-programmed today as I installed the newer model MAF sensor but the power seems to kick in a lot higher in the rev range now. It doesn't really kick in until about 1700 RPM as before it felt like a lot lower down so in turn have to hold it in lower gears longer for hills etc.

Does any one know if this is the characteristics of the newer MAF sensors as from one website I read they have different curve characteristics, or am I just being paranoid?

Hope someone can help.

Thanks!
 

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Legendary BFuk Member
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Hi all,
Had to replace my MAF sensor after my old one was flat spotting alot. Had the ECU re-programmed today as I installed the newer model MAF sensor but the power seems to kick in a lot higher in the rev range now. It doesn't really kick in until about 1700 RPM as before it felt like a lot lower down so in turn have to hold it in lower gears longer for hills etc.

Does any one know if this is the characteristics of the newer MAF sensors as from one website I read they have different curve characteristics, or am I just being paranoid?

Hope someone can help.

Thanks!
And we're talking about what vehicle?

I presume it's the one listed in your car specifications drop down box? Please title your threads as per the forum rules;) You are no longer a newbie and should know better:hihi

:thumbsup
 

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A) First you need to determine if your MAF sensor is 'dead'.
Complete failure is rare: Usually you will experience other symptoms I.e. some or all of the following:-
Very poor throttle response with very slow initial rise in engine revs
erratic or lumpy idle
uneven acceleration even above 2000rpm
the effect of the turbo can hardly be felt
surging or hesitation
juddering and shuddering
reluctance to rev.
smokey exhaust

UNDERFUELLING MAF
Performance below 2000rpm is poor / has recently got worse and the turbo can't be felt until about 2200rpm if at all.
I have to rev up and slip the clutch to pull onto busy roundabouts or there is a heart-stopping delay before it picks-up.
When I open the throttle below about 2200rpm, initially there is a moderate response, but most of the remaining travel is not felt to have any effect.
As the revs pass 2000-2300 the power starts to come in suddenly and quite strongly in comparison to lower rpm. (all or nothing effect)
The engine is very reluctant to rev over 3500rpm even in first gear.
If I unplug the maf connector, the low down torque is much better, though at higher revs it may be worse.
My 50-70 time in top gear is well over what it should be.
I am disappointed with the results of having a remap/chip/tuning box fitted, especially below 2000rpm.
Fuel consumption has fallen somewhat.
My auto stalls easily when pulling away.

OVERFUELLING MAF
Performance below 2000rpm very good - the car is very flexible and responsive
Fuel consumption is poor or appalling
When I open the throttle, there is a delay, then a puff of smoke and then the car accelerates.
The exhaust smells of diesel when idling
Idling is lumpy or uneven and fluctuates up and down
If I unplug the maf connector, the performance is about the same or a bit worse.
In extreme cases, as soon as I touch the accelerator the engine chokes and stalls, with a cloud of black/grey smoke smelling of diesel

MAF OKAY
Performance below 2000rpm is the same as ever
Fuel consumption is normal
I can just feel the turbo from around 1800-2000rpm
However, the engine doesn't like to rev past 3500rpm
I want much better overall performance from below 1500rpm to over 4000rpm
 

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Discussion Starter #4
Sorry A20 RYM its a 2001 320D 136BHP. From the last couple of lines of the previous thread about turbo kicking in at 1800 - 2000rpm it seems to be me!
 

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Sorry A20 RYM its a 2001 320D 136BHP. From the last couple of lines of the previous thread about turbo kicking in at 1800 - 2000rpm it seems to be me!
I shall retitle it for you as it will help attract the members that are able to assist:thumbsup
 

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P.s. I should know better, (Slapped wrists!)
It'll be a slapped arse and 100 hundred lines next time :lol

I must remember to title my threads as per the forums rules!!!
I must remember to title my threads as per the forums rules!!!
I must remember to title my threads as per the forums rules!!!
I must remember to title my threads as per the forums rules!!!
I must remember to title my threads as per the forums rules!!!
I must remember to title my threads as per the forums rules!!!
I must remember to title my threads as per the forums rules!!!
I must remember to title my threads as per the forums rules!!!
I must remember to title my threads as per the forums rules!!!
I must remember to title my threads as per the forums rules!!!
I must remember to title my threads as per the forums rules!!!
I must remember to title my threads as per the forums rules!!!
I must remember to title my threads as per the forums rules!!!

etc:silly


:rofl
 

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You simply need to tell the guy who re-programmed the DDE you want power from 2k revs and he should be able to tailor the curve to suit.
 

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Was it a bosch unit you used or a pierburg one, I replace my pierburg 07 wth a 09 and there is a big difference in low down power....its much better

My be wrong but I dont think you can dial up the way the MAF delivers power via the voltage curve, the difference in the types of MAF are what differentiates the power delivery at particular revs....

all you can do is tell the ECU what power curve you have so it can respone appropriately
 
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