Suspected MAF issue

[Harlowcabbie]

Hi all . I have a w210 e220cdi and its seemed abit down on grunt lately so plugged it into a diag to read live data. The reading i am concerned about is with regards to the MAF i was getting 289 g/s at idle which from reading on sites about mafs is way out of spec . Would appreciatte anyone who could shed a more definite yay or nay on this please. I know mafs arent expensive but would rather not blow the money if i really dont have to.

 

[AMGeed]

Have you tried unplugging the MAF and seeing if there is a change in performance?

 

[Harlowcabbie]

Just took it for a drive maf disconnected and at low revs shes gutless no kickdown. Once the revs have built up she pulls again.

 

[AMGeed]

Just took it for a drive maf disconnected and at low revs shes gutless no kickdown. Once the revs have built up she pulls again.

But is there a difference between the MAF being plugged in or not?

If there is no change, the MAF needs replacing. If there is a big drop in performance, as you seem to be experiencing, then look elsewhere.

I'm not too familiar with diseales so can't really help much more other than to suggest checking for any air leaks. I once had the misfortune to have a diesel van that had a leaking turbocharger hose and it was way down on power.

 

[Harlowcabbie]

Yeah may well have an issue else where but would be interested to know what the correct reading should be at idle for the maf with regards to the g/s reading. Dont know if anyone could help out on that or point me to a site with the correct table.