Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Welung666 on 15 June 2009, 13:39:38

Title: MAF on a TD
Post by: Welung666 on 15 June 2009, 13:39:38
My 99 2.5 TD has the MAF unplugged, has been since I've had it. I plugged it in and it went straight into limp mode, unplugged it and it's fine again. Would a replacement cure the limp mode or would I be better off just leaving it as it is?
Title: Re: MAF on a TD
Post by: zirk on 15 June 2009, 14:26:48
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My 99 2.5 TD has the MAF unplugged, has been since I've had it. I plugged it in and it went straight into limp mode, unplugged it and it's fine again. Would a replacement cure the limp mode or would I be better off just leaving it as it is?

Ive had Maf issues on a TD before, didn't seem to make any difference on mine weither it was pluged in or not.
Title: Re: MAF on a TD
Post by: Welung666 on 15 June 2009, 16:25:45
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My 99 2.5 TD has the MAF unplugged, has been since I've had it. I plugged it in and it went straight into limp mode, unplugged it and it's fine again. Would a replacement cure the limp mode or would I be better off just leaving it as it is?

Ive had Maf issues on a TD before, didn't seem to make any difference on mine weither it was pluged in or not.

This one does matter. Plugged in and it struggles to get up to 1.5k rpm and won't go further. Turbo doesn't kick in until nearly 2k so it's like driving a snail hence me leaving it unplugged :P
Title: Re: MAF on a TD
Post by: charlie on 15 June 2009, 16:28:36
when my maf was broken it would rev freely when not in gear, but when in gear would only go to 2k revs. changed it sorted .PS these are over £200 at the stealers
Title: Re: MAF on a TD
Post by: TheBoy on 15 June 2009, 19:02:56
the substitute values are reasonable, so can drive with maf unplugged.  Slightly more responsive, and far more likely to pass smoke test with working maf though.


Notice, being BMW firmware, the EML doesn't come on, even though it knows there is a fault ;)
Title: Re: MAF on a TD
Post by: semisheen on 15 June 2009, 22:19:14
Sorry to Hijack this post but .......could it be the Maf why im only getting an avarage of "this week" 22.9 to the gallon ?
Title: Re: MAF on a TD
Post by: Marks DTM Calib on 16 June 2009, 11:34:40
Unplug it and see.

The MAF on this unit does little more than limit the fuel injected if the air flow is low to stop smoke (unburnt fuel) exiting the exhaust.

And yes, typical BMW setup, no fault light even if there is a fault!
Title: Re: MAF on a TD
Post by: Stoph on 16 June 2009, 11:39:37
My 525 TDS had the MAF unplugged when I bought it, plugged back in went into limp home mode...which is why the idiot that sold it had unplugged it ! It was sort of ok with it unplugged but undriveable with it connected... with a new MAF fitted its a completely different car... best price I found and with quick delivery too was £157 including delivery from a bloke called Paul. cant remember his trading name but number is 0208 462 2543..  Pull off the old MAF it should be a Pierburg.. code 7.22184.50.0 he will ask you to check before ordering as obviously doesnt want to send the wrong one!

HTH  Chris
Title: Re: MAF on a TD
Post by: TheBoy on 16 June 2009, 18:58:49
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Unplug it and see.

The MAF on this unit does little more than limit the fuel injected if the air flow is low to stop smoke (unburnt fuel) exiting the exhaust.

And yes, typical BMW setup, no fault light even if there is a fault!
It defo responds better with a workign MAF - I had a habit of always forgetting to plug it back in (and no fault light to remind me!), and it was a subtle sluggishness that would remind me...
Title: Re: MAF on a TD
Post by: Welung666 on 16 June 2009, 19:17:29
It's only sub-1500 rpm thats a bit sluggish, I'll have to see about picking a MAF up.
Title: Re: MAF on a TD
Post by: Pitchfork on 16 June 2009, 19:19:37
As I recall, early TDs did not have a MAF
Did that make them more sluggish than the later ones?
Title: Re: MAF on a TD
Post by: Marks DTM Calib on 16 June 2009, 19:21:45
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Unplug it and see.

The MAF on this unit does little more than limit the fuel injected if the air flow is low to stop smoke (unburnt fuel) exiting the exhaust.

And yes, typical BMW setup, no fault light even if there is a fault!
It defo responds better with a workign MAF - I had a habit of always forgetting to plug it back in (and no fault light to remind me!), and it was a subtle sluggishness that would remind me...

Probably because the default is to drop the fueling slightly in order to stop it smoking on a default value
Title: Re: MAF on a TD
Post by: Omegatoy on 16 June 2009, 19:22:30
no it means we can get less faults!!! ;D :y
Title: Re: MAF on a TD
Post by: Pitchfork on 16 June 2009, 19:24:49
What causes a MAF to fail?
What fault code is generated?
Would hydrolocking have caused any damage?
Title: Re: MAF on a TD
Post by: TheBoy on 16 June 2009, 19:55:33
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It's only sub-1500 rpm thats a bit sluggish, I'll have to see about picking a MAF up.
No, its not that, its a subtle lack of responsiveness when its normally in its power band
Title: Re: MAF on a TD
Post by: TheBoy on 16 June 2009, 19:55:59
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As I recall, early TDs did not have a MAF
Did that make them more sluggish than the later ones?
No, as the ecu does things differently