HDi- new MAF consequences

This is the Forum for all your Citroen Technical Questions, Problems or Advice.

Moderator: RichardW

Post Reply
Jodyone
Posts: 121
Joined: 07 Jan 2012, 17:04
Location:
My Cars:
x 1

HDi- new MAF consequences

Post by Jodyone »

After DickieG with his magic box (Lexia) diagnosed a tricksy MAF in my car, I replaced it with one from ebay. His guess was that it might account for a slight thirstiness, apart from anything else. I've since driven almost a repeat journey, at much the same speed (0.85 impulse all the way...), and confirmed expectations fairly precisely: half a tank of fuel had gone further, at 350 miles, lining up for about 400 at the point that we'd seen 340 before. My first 700 mile tank beckons..!

Otherwise, little change (no extra "urge", slightly disappointingly: yes I'm still talking about the car), except that it's less durable against stalling than it was before. I stalled the car three times in the first day or two, having got used to pulling away with no throttle, it seemed so immune to stalling. A few embarrassing moments are fine, but I now wonder if it's a bit prone- a fraction indelicacy with the left pedal has a chance of stalling the car unless I rev it like an old lady who doesn't expect to outlive her clutch..?! A practical proposition for some maybe, but I have hopes.

It's no real problem, and certainly something I can live with (and would rather have for the extra economy). However I wonder if it may indicate a needed adjustment somewhere. Very low-end grunt (1000-1500rpm) does seem a smidge lacking, though it may be that I've just got used to the car and am now expecting more.

The other thing DickieG fixed was the remote locking fob, which consequently revealed an alarm problem. That turned out to be a switch under the bonnet that tells the alarm whether the bonnet is closed or not. It was gummed up with grease and dirt, being attached to a bonnet catch (driver's side) which invariably have gobs of grease over them, for some reason. I removed it and cleaned it up and all is good, finally.
2006 C6 Exclusive, 2.7 HDi
User avatar
DickieG
Monaco's youngest playboy
Posts: 4877
Joined: 25 Nov 2006, 09:15
Location: Buckinghamshire
My Cars:
x 38

Re: HDi- new MAF consequences

Post by DickieG »

If you want to do another lexia session give me a shout.

AFAIK there isn't anything that can be adjusted to improve the stall issue as everything is controlled by the ECU but what may be worth a look at is to compare the readings on Lexia with your new MAF and my spare stock genuine Citroen one to see whether there is any difference.

As for the alarm it can be turned off with Lexia if it's waking up your neighbours.
13 Ram 1500 Hemi
14 BMW 535D Tourer
19 BMW i3s
06 C3 Desire 1.4
72 DS 21 EFi Pallas BVH
RichardW
Forum Treasurer
Posts: 10812
Joined: 07 Aug 2002, 17:12
Location: United Kingdom
My Cars: MK2 '17 C4GP 1.6 BlueHDi 120
'13 3008 1.6 HDi GripControl
x 983

Re: HDi- new MAF consequences

Post by RichardW »

Jodyone wrote:Otherwise, little change (no extra "urge", slightly disappointingly: yes I'm still talking about the car), except that it's less durable against stalling than it was before. I stalled the car three times in the first day or two, having got used to pulling away with no throttle, it seemed so immune to stalling. A few embarrassing moments are fine, but I now wonder if it's a bit prone- a fraction indelicacy with the left pedal has a chance of stalling the car unless I rev it like an old lady who doesn't expect to outlive her clutch..?! A practical proposition for some maybe, but I have hopes.
Interesting.... I have recently replaced the MAF on our Picasso HDi with a cheap one from e-bay (prob the sam seller..!) and have noticed an increased propensity for stalling. No extra revs are needed as such, just a bit of throttle to prevent a stall. The performance of ours has been transformed, so we can live with the possible stall issue - especially given that the replacement was £40 and Cit original is 4 times the price.... :evil: There can't be much to the electronics, perhaps I will open up the box on the old one, and see what's in there.
Richard W
Jodyone
Posts: 121
Joined: 07 Jan 2012, 17:04
Location:
My Cars:
x 1

Re: HDi- new MAF consequences

Post by Jodyone »

DickieG wrote:If you want to do another lexia session give me a shout.

AFAIK there isn't anything that can be adjusted to improve the stall issue as everything is controlled by the ECU but what may be worth a look at is to compare the readings on Lexia with your new MAF and my spare stock genuine Citroën one to see whether there is any difference.

As for the alarm it can be turned off with Lexia if it's waking up your neighbours.
Thanks. I'm pretty full-on at work, but if I get a chance one evening or weekend I'll call you in case you're around. The alarm has been ok, as described- except, weirdly, for today! It went off in the work car park twice..! Turning off the internal sensors stopped another occurrence, so maybe they're not above suspicion after all. If we do manage to meet again I think turning the damn thing off for good would be a good idea.

RichardW- that's interesting to hear. Your description is pretty much my experience (without the extra oomph). Part of me wants to think that the turbo spooling is more evident at 1500-2000rpm as well, though that is probably just because I'm listening for anything new. I've never driven a similar car, so I don't have anything to compare it to. However, in general it drives very well, more than rapidly enough, now even more economically, and only really stalls when it's probably my fault.
2006 C6 Exclusive, 2.7 HDi
citroenxm
Posts: 8061
Joined: 30 Dec 2004, 23:10
Location: Somewhere in North Wales, Anglesey
My Cars: M reg Xm S2 2.1td Auto Exclusive. 269k and rising
L reg XM S1 V6 12v Manual SEi
L 94 XM 2.1 TD auto total resto

2008 Peugeot 207 Sw 1.6 16v hdi. 217k and rising
2010 Peugeot 207 SW 1.6 8v HDi 161k and rising
x 70

Re: HDi- new MAF consequences

Post by citroenxm »

My 110 is hard to stall! I can pull up on the clutch ALONE, boot full of my tools on a 30 deg incline...

I find this a handy thing when it comes to reverse parking on a flat road... clutch and brake and no accelleration needed.
Sharing a pug 207 1.6 hdi Sw 16v.
M reg Xm 2.1 td auto exclusive S2 269k and rising
L reg XM V6 12v SEi auto .. Light project

A very sad...
1994 XM 2.1 d auto
steelcityuk
Posts: 1053
Joined: 03 Jul 2006, 21:51
Location: not applicable
My Cars: not applicable
x 1

Re: HDi- new MAF consequences

Post by steelcityuk »

I was told to buy MAFs only from a main dealer due to the number of fakes out there that don't meet specification, don't know how true it is but the source of the info was a diagnostics specialist that had a page or two in a motoring mag. The Xantia I had was gutless at low revs and wanted to stall trying to set off but was good on fuel whereas the C5 didn't need any revs to pull away.

Steve.
not applicable
Jodyone
Posts: 121
Joined: 07 Jan 2012, 17:04
Location:
My Cars:
x 1

Re: HDi- new MAF consequences

Post by Jodyone »

steelcityuk wrote:I was told to buy MAFs only from a main dealer due to the number of fakes out there that don't meet specification, don't know how true it is but the source of the info was a diagnostics specialist that had a page or two in a motoring mag. The Xantia I had was gutless at low revs and wanted to stall trying to set off but was good on fuel whereas the C5 didn't need any revs to pull away.

Steve.
Hmm. That's interesting to read and about describes my experience. The Lexia will reveal all- maybe I'll really try to get to DickieG if he's available and measure them. Between us we have three- my old errant MAF (i've brought it with me); one new cheap one (currently fitted); and one genuine one (his). An all-else-even comparison might be revealing.
2006 C6 Exclusive, 2.7 HDi
Post Reply