Hello all,

 

I'm trying to diagnose an intermittent problem with my sisters car (Fabia 1,9 TDI PD100).  She reports that every now and then it has no power (I assume goes into limp mode) but having scanned the car with VCDS lite there are no stored codes.  Looking at measuring blocks for the turbo and injectors, everything looks OK.

 

I wondered if it could be a failing injector loom but someone else told me a failure would result in a fault code.

 

I'm about to replace the fuel filter but its only 5k old.

 

So... I'm thinking MAF.  This was replaced by a garage about 6 months ago after having similar issues and a stored log code.  The bill was about £60 so when I was told this, thought it must be a cheap £20 Chinese part.

 

I've done some logs using her laptop and VCDS while she applied WOT in 2nd and the results look OK.  Actual roughly matches specified but I'd be grateful if others could take a look at the data below and confirm this looks OK?

 

I'm also wondering if the MAF readings sometimes go astray and therefore cause limp mode but since the MAF isn't 'faulty', it's not actually storing a fault code?  Does this sound plausable?

 

https://dl.dropboxusercontent.com/u/9932810/PD100%20MAF%20Logs.xlsx (Link to logs)

 

Any advice appreciated.  Many thanks

 

 

No, you're barking up the wrong tree, changing the fuel filter will do nothing and the MAF looks fine. Log boost to see if there's any overboost, it looks like there may be.