if A/F go lean; would EGT rise?

[isnms]

I had read - Leaning out AFR increases EGTs, along with a lot of other info that I can't seem to correlate with my log.


I wanted to try a little more boost, so I upped it to ~13 psi (.90bar).
Did a down shift from 4th to 3rd and when I viewed the log it scared the crap out of me.
Note this happened back in April. I lowered boost and I haven't had any engine issues or experience this since then.

I just wanted to get some input on what may have caused it and why EGT didn't sky rocket.

• failing wideband sensor - mine is nearing 3 years old.
• not enough fuel - I will install my fuel mods before I increase the boost again.
• other...

boost spiked to 14 and leveled to ~12.5psi,
boost was 12.5psi when A/F shot up when around 4900 rpm,
EGT was ~1517°F when A/F shot up, then maintained ~1500°F after

I have never seen this at ~11.5 psi (.80bar), which is what I backed it back down to and has been ever since.

 

[tissimo]

you would of miss fired if it went that lean.. your sensor stopped working.. i'm sure a/f was fine..

 

[isnms]

That puts me at ease. Failing sensor was my first thought.
Thanks.

 

[MKIIINA]

whats the bottom of the range that the sensor reads to? im with tiss on this that the sensor died on ya but would be nice to know the min it would read. any data after that point?

 

[isnms]

I have seen it register low 9's, had a rich issue