air fuel ratio at WOT

[showtime3492]

Just got my wideband installed and finished wiring it in. So before I drive the jeep what do you guys classify as safe or optimal air fuel ratio at wot?

[604rail_king]

assuming your NA, 12-13.0 without any audible pining

any higher afr's means you're lacking fuel, lower means your running rich.

under normal cruising you should be 14.5-15.5

[SilverXJ]

x2

[showtime3492]

Thanks! I'm gonna try to road test my xj for the first real time in over a year tomorrow so should be interesting

[showtime3492]

Hey guys.
Back with some more questions. Got my wideband installed and the interior of the jeep buttoned up and decided to start it up tonight and see what was goin on with it.

Initial start up yielded Airfuel ratio bouncing around between 14.3-15.8 that was on a map adjusted voltage of 5.35v

Cranked map voltage up to 6.20v and it held around 13.6-15.2
bouncing around fairly erraticly.
Have vids of the guage ill post.

My intitial questions are.
1. i thought that the map adjusted voltage did not kick in untill at above 80% throttle?
2. What is going on here seems kinda crazy
3. How screwed is it? lol

[SilverXJ]

If make some time to lean it out, or you are pushing it out of range and the PCM is fighting it.

[showtime3492]

If make some time to lean it out, or you are pushing it out of range and the PCM is fighting it.

I even ran it at stock and it was all over the place. I unpluged the map sensor while running though and that settled it down substantially it hovered around 14.4-14.9 pretty closely

[showtime3492]

http://www.facebook.com/anthony.sherida ... 0146647580
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[showtime3492]

If make some time to lean it out, or you are pushing it out of range and the PCM is fighting it.

It is like it isnt even using closed loop it just goes right to open, even before it is up to operating temperatures.

[SilverXJ]

Whats your vacuum at idle?

[showtime3492]

Whats your vacuum at idle?

Not sure. Do you know where to find a cheap tester? And how do you test the vacuum?

[Cheromaniac]

Initial start up yielded Airfuel ratio bouncing around between 14.3-15.8 that was on a map adjusted voltage of 5.35v

Cranked map voltage up to 6.20v and it held around 13.6-15.2
bouncing around fairly erraticly.
Have vids of the guage ill post.

My intitial questions are.
1. i thought that the map adjusted voltage did not kick in untill at above 80% throttle?
2. What is going on here seems kinda crazy
3. How screwed is it? lol

I think you've cranked the MAP voltage up too far. The AFR should fluctuate in a narrow range around 14.7 when the engine's at hot idle or when cruising. Yours is fluctuating more wildly which suggests that the PCM is working hard to lean out a mixture that you've set too rich to keep it around 14.7, so I suggest you return the MAP voltage back to 5.35v and work from there.
The PCM will only go into rich open-loop mode during warm-up and heavy acceleration. At WOT you should be aiming for ~13.0 over as wide an rpm range as possible.

[CobraMarty]

What is your MAP output voltage with the key on engine off?

[showtime3492]

Initial start up yielded Airfuel ratio bouncing around between 14.3-15.8 that was on a map adjusted voltage of 5.35v

Cranked map voltage up to 6.20v and it held around 13.6-15.2
bouncing around fairly erraticly.
Have vids of the guage ill post.

My intitial questions are.
1. i thought that the map adjusted voltage did not kick in untill at above 80% throttle?
2. What is going on here seems kinda crazy
3. How screwed is it? lol

I think you've cranked the MAP voltage up too far. The AFR should fluctuate in a narrow range around 14.7 when the engine's at hot idle or when cruising. Yours is fluctuating more wildly which suggests that the PCM is working hard to lean out a mixture that you've set too rich to keep it around 14.7, so I suggest you return the MAP voltage back to 5.35v and work from there.
The PCM will only go into rich open-loop mode during warm-up and heavy acceleration. At WOT you should be aiming for ~13.0 over as wide an rpm range as possible.

Thats what i thought so i left it at the factory 5.0 voltage and it still did the same thing. The first time i unplugged the map however it ran better, sequential times after wards though it wanted to go lean. it did this at every voltage i set it at from factory -6.2

[showtime3492]

What is your MAP output voltage with the key on engine off?

It was higher than i thought it would be it was 5.13 at the factory setting before map adjuster.

Really need some help to get this thing figured out. TIred of seeing it sit unable to move. Thanks guys!