Finaly fitted my wideband AFR gauge...

[S3 Paul]

Well, ive had it a year now, i decided the weather was good enough for me to have a crack at fitting it,
Im about to go out for a drive, What Numbers should i be seeing?
The car has a hybrid turbo,
decat 3 inch down pipe and miltek system,
FMIC
Jetex air filter
other bits and bobs...
I understand Vag cars run lean when starting to make boost whats safe and what shows a possible problem??

 

[<tuffty/>]

Normally go a bit lean to help boost but should then plummet to mid 12's (0.85 lambda) on boost for best/safe power

<tuffty/>

 

[S3 Paul]

I think i read somewhere something about ...
11.8 to 12 on boost?
cruising should show around 14.7 to 15?
high 12s on cold start??

I think that was for a mapped TT so should aply??
Just another gauge to make me paranoid !

 

[<tuffty/>]

12.5 afr on boost mate... any richer kills turbine energy and power will drop... should help keep egt's down too...

<tuffty/>

 

[<tuffty/>]

Air-fuel ratio - Wikipedia, the free encyclopedia

<tuffty/>

 

[S3 Paul]

Thanks buddy

 

[S3 Paul]

Well something i didnt expect...
When the car is on over run ( reving down in gear down hill ) the AFR reading goes to full lean. 22.4
Im guessing the injectors shut off ? They come back on again at 1200 rpm or the slightest touch of the throttle.
Makes sence but a little wierd the first few times it happens.

 

[DaveA3]

so what were the other readings all good?

 

[S3 Paul]

Ye, I will make a note of them later, But a mate who knows a thing or two about tuning turbo cars said its all good.
Im not sure wether the figures should be the same on all cars but... good and safe will do me !

 

[<tuffty/>]

Well something i didnt expect...
When the car is on over run ( reving down in gear down hill ) the AFR reading goes to full lean. 22.4
Im guessing the injectors shut off ? They come back on again at 1200 rpm or the slightest touch of the throttle.
Makes sence but a little wierd the first few times it happens.

Yep.... let off the throttle with the clutch engaged in gear etc and injectors switch off... the ECU does this to help fuel economy...

<tuffty/>

 

[camscockle20vT]

Yep.... let off the throttle with the clutch engaged in gear etc and injectors switch off... the ECU does this to help fuel economy...

<tuffty/>

Do you know if this is on all the 1.8 20v T mate?

 

[S3 Paul]

I seem to think its only on the later drive by wire cars?
I may be wrong though