gonna install my boost meter and air/fuel meter..is it true you need to install a new O2 sensor?
 

for the Air/Fuel meter that is....whats wrong with connecting it to the stock one? any advice would be appreciated thanks.... I have a 97' A4....

No u don't.. U can tap off the existing precat O2.

but my friend with a 1.8T VW said he had to because it would damage his stock O2 sensor
 

i didn't under stand how an air/fuel gauge could damage your 02 sensor but apparently thats what the shop told him....and thats the same shop i'm planning to do my install..they specialize in german car tuning....

What an A/F gauge really does is it monitors the O2 signal voltage.
 

I don't see how that would damage the O2 sensor. Sounds like they're trying to rip you off. Time to go to a different shop.

I dunno about damage...but the OEM sensor is a POS compared
 

to an accurate device...you can't trust the OEM O2 sensor at the ends of it's range (Rich/Lean) it's only really accurate around Stoich...this is why the car goes Open Loop and onto fixed maps at WOT as you could not rely on the stock O2 sensor to guarantee proper stoichometry...least that's what I've been told.

Since most of us can't afford one of those Horiba high band O2 sensors (which are good at the extremes) the next best is the Greddy AF gauge which comes with a near high band O2 sensor...these types have a very limited lifespan though...a Horiba is good for maybe a few hundred hours methinks...but the Greddy one is good for...uhh something like 2000 Hours I thikn that's what they claim.

Regards,

James R.

True...
 

OEM sensors are not accurate at the extremes but for out application it's more than good enough. The reason most of us need an A/F gauge is for monitoring reasons not for tunning reasons. OEM O2 is not good at telling what the exact A/F is at the extremes(sensitivity looks like a Tangent graph) but it's fine detecting whether the A/F is lean or rich. So if the stock O2 says the mixture is lean at WOT you know something is wrong.

Definately install a dedicated sensor for the air/fuel meter!!!
 

I ran off my stock O2 sensor in my previous car and was constantly burning them out! Go and buy a bosch universal O2 sensor for $35 and use it instead. then if it dies your car still runs properly and all you have to spend is $35.

wait i don't get it? how can a meter damage a O2 sensor?

True dat about the lean thing...I just mean that the OEM O2 sensor is no good for absolute...
 

and if your O2 meter tells you you're not lean you could still be a little lean becuz the sensor can't be trusted. I hear the Greddy one is nice...looks good, but it's a lot more expensive than a Haltech or something like that...but for good reason the sensor alone is $$$

Regards,

James R.

Won't damage jack $hit I was just saying it's not a lab grade instrument so don't try to tune with
 

it.

Regards,

James R.