O2 sensor help needed asap

[Maltman]

I really need help with this problem....please.

I recently had issues with the O2 sensor acting wrong at the track and I'm not sure if I need a new one or if there is something else going on. Every time I go to wot, the O2 voltage dropped to below 50 and stayed there. However, during idle and moderate throttle, the voltage seemed to jump around like it should.

I had this problem tacked on to my old post about tlink data involving poor idle and blms. I have attached the latest 1/4 mile runs to my website - here

I don't want to just go out and order a new heated O2 without knowing if I'm missing something else. If you can please take a look at the tlink files and let me know if you see something messed up, I'd appreciate it big time. I want to get this thing to the track this coming Friday for a retest.

Note this post for further info if needed: http://www.turbobuick.com/forums/showthread.php?s=&threadid=126735

Thanks in advance,

 

[azgn]

the 02 sensor has no input at WOT

makes no difference .......at all

 

[Maltman]

Ok...didn't know that...thank you.

However, how is everyone tuning their car at wot? I know something is not right on this car.

I seriously doubt I'm running that lean or I'd be towing the car home in pieces. If you look at those files you'll see the weird numbers I'm getting....and on some of those frames the tps indicates I'm not even close to wot (probably because I felt nervous mashing the peddle knowing I didn't have a clue to where this thing was running).

 

[BoostKillsStres]

I had a very similar situation once when running alky with a standard O2, sensor would start the run in the mid 700's then fall to almost nothing from just into the run all the way through the run. Replaced sensor and haven't ever seen it again.

 

[sweetv6]

Check for a proper ground
-batterie to engine
-engine to frame
-engine to body
-engine to alternator

hope it help

Claude

 

[azgn]

you can use the 02 readings at WOT to help tune your car, but all they are are readings, they don't affect your performance at all

the 02 is not all that accurate but it is better than nothing

(knock sensor, egt, WB 02, plug reading are other things that can be used)

 

[Maltman]

Ok...I'm getting sick of this fast!!!

I have more grounds than what the car came with from factory. I added a ground to the DIS and 2 more engine grounds (1 to the frame and one to the body) awhile back.

So I don't think I'd be lacking in that department.....unless there is a chance I'm "overgrounding"?

Also, a new sensor was put in (heated) today, went for a spin and same crap!!

O2 bottoms out so I have no idea where I'm running. Worst, my blms STILL climb to 150 at idle!!!!!! Could the O2 sensor not be getting a good ground at wot? ...I believe it relies on the egr system ground or something like that.

I checked the egr crap and found that there is a small leak when vac. is "directly" applied to the valve "and" solenoid. It didn't seem very big since the vac. guage slowly fell to zero...but shouldn't it hold a charge (especially the valve since it's only job is to respond to vac)?

Otherwise, I chased everything that could be causing the blm rise that I know of....but who cares, I can't tune it and I'm can't afford to invest (nor do I have the time to install) and egt gauge.

Mark

 

[Lee Thompson]

ground

There is a small tan wire that attaches to the back of the pass. side head. This is the ground for the O2 sensor. Leaving that wire attached, make a new wire, ground it anywhere to the eng. and run it inside to the ECM and piggy back it onto the old wire where it goes into the top of the ECM. Let us know if this helps.