Bad Wideband O2 sensor?

[carbuff]

Hi guys,

Can anyone tell me if there is a conclusive way to know if my O2 sensor is bad?

I seem to be having an overly rich problem that I can't solve. I've leaned things out quite a bit, but it's still rich. I just pulled the cylinder heads (another rebuild, joy...) and the piston tops are CLEAN! I mean, no carbon... To me, that's a very rich condition.

The Dashboard on my FAST system doesn't show any problems. The UEGO voltages seem to be where they normally are.

Is it possible for the O2 to go bad but the voltages to be inline?

And, in case I do need to but a new one, where is the best place to purchase, and what is the going price?

Thanx!
Bryan

 

[bruce]

Originally posted by carbuff

Can anyone tell me if there is a conclusive way to know if my O2 sensor is bad?

Is it possible for the O2 to go bad but the voltages to be inline?

And, in case I do need to but a new one, where is the best place to purchase, and what is the going price?

Plug in a WB meter (with it's on sensor) and see if the voltages match.

the can be poisoned, and go weird.

Far as I now only thru FAST or a retailer of their's. You just can't plug in any ol sensor and have it work.

 

[bobc455]

Bruce - does Summit sell a WB meter?

Bryan- what sort of A/F mixtures are you seeing - are you pegged at 9:1? And I'm confused why you think that super-clean pistons mean that you are super-rich... doesn't running so rich give you carbon on the pistons? How did the plugs look?

Just want to make sure you're not fighting a problem that isn't there, or that's down a different path from where you're headed...

-Bob Cunningham
bobc@gnttype.org

 

[carbuff]

Bob,

My thinking was that the piston tops were so wet that carbon was washed off. I seem to have such a strong gas smell when the motor is running also, even though the Dashboard shows my requested AFR (about 13.8) at idle. There are no cats on the car, so I realize I'm going to have some smell, but it seems excessive to me. Maybe not?

Bryan

 

[bruce]

Originally posted by bobc455
Bruce - does Summit sell a WB meter?

Not that I've heard of.
Do you have a pal locally that has one?.
Bump come to shove, building a DIY-WB is one answer.
DIY-WB.COM
$20 in parts and you're set

 

[norbs]

More than $20 in parts for sure about $120

 

[10SV6]

If you've got a cam with lope at idle - random cylinders missing every once in a while, you've going to have a rich smell. I've got a corvette with a decent cam. The exhaust smells rich. 2 different widebands show it's idling at 14.7. Too lean for the cam but the stock ecm is commanding the A/F.

Get access to a second wideband to double check, but I'd guess with the UEGO voltages being in the correct area, the wideband is working properly.

 

[Craig Smith]

If it smells rich at idle but reads lean, that could certainly be due to the big cam/big exhaust thing. The sensor simply doensn't get a good airflow signal at low engine speeds in a pumped-up motor. It is quite common to get a lean reading under these circumstances. Follow your nose at idle.

 

[bruce]

Originally posted by norbs
More than $20 in parts for sure about $120

I bought several parts kits for $17 US.

 

[norbs]

the kit is OZ one, with a display and case everything with shipping included, not the DIY one, looks hokey pokey