Just lately my 2004 1.8 focus tdci had felt rather flat before coming on boost and also seems to have shit mpg. Ive just covered 240 mile on 40 quid which isnt brilliant considering ive been driving steady.
So out of interest ive just disconnected the maf and took it for a drive and its feels alot more perky seems to rev alot better and smoother also.
Would this indicate a faulty maf or is there another way of testing it. It looks to be clean inside and i give it a quick blast with carb cleaner but it has made no difference.
Ive left it disconnected for now to see if i get a mpg iprovement but am i risking causing any damage ?

 

I think this is a common problem, IIRC if it won't rev past 4000RPM but think I may be thinking of the petrols but obviously it's more prone to "Gumming up" on Dervs. Yes you are supposted to clean with cleaner whilst being very careful as the wires are delicate.

Do the Diesels not use a MAP sensor as there FI, I certainly know one of the varients does either the DI or the CI?

To answer your question yes, as the ECU will be missing one of it's inputs and so won't be able to make correct calculations, I would of thought this would bring the EML on as well?

Martin

 

Just checked my bible and it says that all Diesel engines have a MAP sensor?

Martin

 

Hi the car seems to pull through the rev range fine although seems more smooth without the maf connected. Ive got no eml on either. Its the lack of performance below 2000 rpm that seems to increase tho with the maf disconnected which i thought pointed to fautly maf especialy with the poor mpg aswell.
Not to sure about the map sensor tho what is that supposed to do does than not read the boost levels.
thanks

 

Well ive spunked £144.26 on a new maf from ford and the car has improved no end. It now pulls really well through the revs with no hesitation and im hoping the mpg improves to.