Lambda failing?

[Mark@VAGWORX]

Will you always get a fault code if one of the Lambda probes is failing?

Reason i ask....

Logged my MAF readings the other day. Was only seeing 130g/s, but the car still pulls hard and goes really well.

I've since tried 2 new MAFs. I've logged them and seen higher values, 145-150g/s....but.......the car runs like a bag of spanners. Massive amounts of lag, and then goes like the clappers when i finally get boost. But, as the car gets hotter, it runs worse and worse to the point that it even stalls.

Now, is this due to a dodgy Lambda, rather than a dodgy MAF? Just thought that is the new MAF is flowing higher values, then a dodgy Lambda is not controlling the fuel/air mix very well.

Any suggestions?

 

[PhilW]

Any fault codes to start with?

 

[Martyn]

I'd run on the higher reading MAF but reset the ECU (and a TBA) after fitting as the fuel trims will still be running on values adapted for the old MAF.

 

[Mark@VAGWORX]

I disconnected the battery, for 10-15 mins and reset the ecu. I thought it auto aligns the TB during this process?

I've had no faults codes, and i've still got no fault codes.....

 

[Martyn]

TBA will only occur if you have the bonnet and drivers door open whilst turning the ignition to the first stage (you'll hear the high pitched noise).

 

[Mark@VAGWORX]

Yeah, sure i did.

Can you reset the TB through VAGCOM itself?

 

[Martyn]

http://www.ross-tech.com/vag-com/cars/throttlebody.html

 

[Mark@VAGWORX]

cool. thanks