21:1 Afr

[VWTUNING]

Am I mistaken in thinking that if my car was really running this lean I would not make any power?

I believe my wideband sensor is hosed and reading off but seeing that scares me. The car pulls good though so thats the main reason I think its just a bad sensor.


Is my thinking correct? Or is my car about to blow?? :P

[boostin20v]

I hope to god thats a bad sensor and not what you're really running!!!!!

[VWTUNING]

in my old 2LT the car would fall on its face if I hit 16:1 (when my wastegate stuck closed and I overboosted), so I dont think the sensor is reading correct.

I hear no pinging and the car pulls hard...

[USOPHUNKE]

is this number a constant in boost? whats it read at normal driving? idle?

[BUNNYLOVE]

If it would even run at all that lean you would see some ill effects atleast. i would say your sensor is hosed.

[VWTUNING]

Thats what I have been thinking. Any one know where I can get a mk4 wideband sensor cheap?


is this number a constant in boost? whats it read at normal driving? idle?



its very erratic, usually reads rich though.

[evolveVW]

I dont think the car would want to run at all at that AFR. The only time a FI motor should be that lean is in off throttle deceleration. I run 15-16:1 in vacuum at part throttle on the highway, any leaner she'll let me know. As soon as I'm on it , AFRs are in the 11:1 range the whole way to redline.

So- yeah your sensor is shot.

[WickedWabbit]

Is there a gauge ground that possibly could be bad, making it erratic?

[VWTUNING]

the display and MAP sensor seem to be working fine, so I dont think its a ground issue.

[WickedWabbit]

Check these yet;
Running Lean – VAC Leak, MAF, O2 Sensor, Fuel Filter and fuel lines

Also

Here is a link where a guy has the same problem, some of the info may help give you ideas. (http://www.corral.net/forums/showthread.php?t=761616)

[B4passatglx]

what RPM are you at when you see those lean numbers? Your fueling kit should support up to 9psi I think it is. You'd be misfiring pretty bad if even running at all with those numbers! that is scary though

[WickedWabbit]

Any luck or progress?

[VWTUNING]

Well I dont believe the car is really running any where near that lean; in my experience a car can not make power that lean. I strongly believe I just have a bad O2 sensor so im trying to find one to swap mine out with and test.

thanks for the input/links though, I appreciate it.

[VWTUNING]

Any one know where to find these o2 sensors cheap?

IIRC its a MK4 wideband sensor.


Jason found one for $63.97 shipped (http://parts.ajusa.com/ajusa/stores/quote2.jsp?partner=ajusa&year=2001&make=VW&model=JET-GLX-002&product=C5010-89310&application=000470968&category=C&shocks=null&partnerSession=967a063386db544f9c415d468c142ac4) which I think is a good price. the manufacturer of my wideband sells em for $90 shipped.

[BUNNYLOVE]

Seems like a good price to me. I checked my normal places and most were $5 more.

[Jackalope]

Wish ya luck. No pic-n-pull part just to see if you're right, then get a new one if it is?

[VWTUNING]

Some one pulled one of these out of a Subaru at the shop for replacement, Im thinking about trying the old one for S&G...