O2 Sensor Placement?

[ddahlgren]

I realize I can be vague at times or cut straight to the point as well. Sometimes I may come across as either rude or a know it all also, in my defense I have been at this racing biz for over 40 years.. over thirty in professional racing and winning for that long as well. I drove a few times and while ok at it never thought I would be up to my personal expectations so opted for the engineering side rather than the driving.. It can give you a short fuse at times or the assumption that everyone knows what I am thinking and all the background info that goes with it. In short my brain skips past the obvious for me and goes for the conclusion only and not how I got there. So I hope everyone knows there is never any offense meant if the answer seems short and a just do it my kind of response. My real goal is to have no one waste a lot of time on the esoteric if there are no results at the end of the road.. even worse not have to bleed a ton of cash going down a dead end road I did a long time ago.
Dave

[Sumner]

Dave and Harold thanks for all of that input.  Since I barely made it through 1 year of chemistry I was lost through most of it, but I'm sure some of the guys on here understood more than I did.

I'd like to comment on how we are using air/fuel readings with the stude.  We are not using them to try and make HP.  We are using them to keep the air/fuel in a range where we think the engine will more likely stay together.  I've talked to very few people that have run blown gas with mechanical fuel injection and a roots blower and without an inter-cooler that have been able to run to the 5.  I think we have been successful so far since we keep the motor very rich in the 9.8 to 10.5 range and we are cooling it with the unburnt fuel.  I might be wrong, but that is my take on it.  Sure we could make more HP if it was probably in the 12.5 to 13.0 range, but what is the point if you can't run the whole course or at least enough of it to get to speed.

I'm very confident in the LM-1 getting us an accurate enough reading for what we are trying to do and a lot of people use them along with their computer on an EFI motor to fuel the motor following the wide band output of the LM-1.  I'll do that with my lakester motor eventually.

As far as the partial throttle thing.  In 1st and 2nd when we see no more than 25%-30% throttle I'm not very worried about the motor being lean there.  I have been concerned when he is running over 230 and has to feather the gas due to course conditions and starts running 60%-90% throttle for a period and the motor is still under a big load.  If it starts getting lean then, and it has, then there again we need to think about maybe making changes.

Anyway we are still in the baby learning stages compared to your guys experience, so I appreciate all the input.  Gives me something to think about and just might help us go faster.

c ya,

Sum

[Harold Bettes]

Sum and All,

I think the point that I got out of Dave's inputs relying on his years of experience was that the Lambda sensor can give you a relative number not necessarily one that is an absolute.

The repeatability of the readings so that you can see the trend change is more important than the absolute accuracy. So if you make a jet or pill change (or change in the fuel map for EFI stuff) then you can rely on the relative change as an indication.

If that is not correct, Dave will make his comments accordingly.

Regards,
HB2

[suzi]

Here is something I dug up off the internet. They are talking about a 2002 Sonata:

"It's a problem with your bank 2 upstream oxygen sensor. First, call the
dealer back with your vin and have them check to see if there are any
recalls on the vehicle. There was a recall to reprogram the pcm which
addresses this issue. If this hasn't been done, they should be happy to do
it free of charge. If it has already been done and you're beyond the
warranty period, the repairs are your monkey.

Hyundai has had some problems with these oxygen sensors and has made some
attempts to fix the problem. Although they originally appeared to be
working, I still see many failures of this oxygen sensor.

If you'd like to try this job yourself, it's the oxygen sensor in the
front manifold near the top. The part number for the sensor is
39210-3916A, but be aware that the distribution of this sensor is
currently being restricted by Hyundai because they don't have enough to
fill all the orders. I actually checked into the availability of this
part a few days ago and it appears plenty should be available in about a
month."

[suzi]

When I googled Bank 2 sensor 1 a post(not Hyundai related) indicated the sensor was on the driver side before the cat converter. That was not it. It is the one as you said and have indicated on the drawing at the front of the engine. This is a XG350.

[Stainless1]

suzi are you a spam bot.... your posts are nonsense on an old thread....