406oc.co.uk

Fitted a new VDO MAF (to a 2.2 diesel) and whilst it's better, there's still an issue with acceleration / power output on steeper hills.

Still flat acceleration in places but not as flat as before...

Certainly not as good as the 'new car' type acceleration with the MAF plug disconnected.

It can be a journey getting to the bottom of issues

I would be tempted to send it back claiming it's faulty and run round with the old one disconnected
If your happy to
Did it make much difference to your fuel economy
Are you sure it was a 'new genuine V.D.O Siemens one '

I ask that as I bought a 'new one' off ebay , it came wrapped up in cellophane, was dusty under the cellophane & no
genuine box

There's loads more to check out

dirtydirtydiesel wrote: ↑Wed Apr 10, 2019 10:52 pm Did it make much difference to your fuel economy
Are you sure it was a 'new genuine V.D.O Siemens one '

Fuel economy looked to be the same.

It came in a VDO box, with Continental tape sealing the box, there is also a hologram sticker on the box. The actual part itself has the same part number as the one removed, stamped on the underside of the casing. The only difference is the original one has 'Siemens Made in Germany' and then new one has 'VDO Made in Germany'

ows-cdn.tecdoc.net/vdo/home.jsp?

It's quite a bit better on normal roads, going up steeper hills is the main issue with flat acceleration. So I don't think it's the MAF itself, somewhere downstream from the signal going from the MAF to the ECU.

Anyone reading this, with MAF issues, before shelling out £100 on a VDO MAF, you might want to get hold of another MAF that's the same for testing purposes off someone you know with a 406. They can be changed over easily with a larger Philips screwdriver and a Torx 20 one.

Where abouts are you?

Could do with someone who knows what a sorted one feels like going for a spin in it
Ginger or Doggy spring to mind

The 2.2 has quite a lot of complexed vacuum plumbing with can be 'corrected'
Also the variable vanes in the turbo are know for sticking at higher millages

As I said before theres quite at lot it could be

If there is no fault lights on, I would suggest an injector cleaner and better quality diesel for a couple of tanks - and drive it hard for a while.....
I'm happy to put it on diagnostics if you are local to Bournemouth.

GingerMagic wrote: ↑Thu Apr 11, 2019 5:55 pm If there is no fault lights on, I would suggest an injector cleaner and better quality diesel for a couple of tanks - and drive it hard for a while.....
I'm happy to put it on diagnostics if you are local to Bournemouth.

Not near Bournemouth but cheers anyway. Currently have the MAF disconnected again and it throws up an EML light after day 2 of it being disconnected. Not a limp home mode fault though. No EML light comes back on once you re-connect it. The engine feels really responsive with it disconnected and the fuel economy seems a bit better Does the MAP sensor take over the MAF sensor role with no MAF connected?

On a 2.2hdi, yes.
How about unplugging the MAP and connecting the MAF?
Just for curiosity really....

Puzzling this - I've never managed to get a 2.2 to run anything other than really badly with the MAF disconnected.
Mind you I have never tried it on a car with the standard ecu map, maybe that's the difference?

Its been a while since posting about maf sensors , but I also found out when I went to get the exhaust replaced that I had the wrong one on. Now have the right one fitted and mpg has increased a little. Also got that guy on ebay that repairs the com2000, I drove down to him and he fitted a delta that is by him a better make. Gave me a twelve months guarantee. good bloke. Have not fitted the blanking plate yet, too cold to be working on cars at present. What about blanking of the vacuum pipes that operate this valve thing ? Anyone have any pictures of this done ?