Why am i rich when i am towing?

[Mr. Smelly Gas]

So i have a supercharged l9h denali, when i am pulling my car (at cruise <50% tps) i noticed my afr are <13.0. I disabled the PE so the only thing i can think is its going into open loop. It seems like more boost the fatter it is, all the way down in to 11's... I guess what i am asking is: why is this going on? Why is not stoich?

[schpenxel]

Post tune

Post log

[Mr. Smelly Gas]

OK I didnt have my WB hooked up cant find the adapter, but going by the O2's you can tell when it gets fat, I quess thats what it doing. I know have alot of KR I just pulled some timing for my towing tune too... My truck empty is always at 14.7 until I go WOT. I also get 20MPG empty and towing i get 8 MPG


denalitowing.hpl

miketowingtest.hpt

[schpenxel]

What MAP sensor are you running?

Add commanded AFR to your logs next time

Also I'd try disabling cat over temp protection, worth a shot

You're seeing a ton of knock also

[Mr. Smelly Gas]

I am using a Bosch TMAP 2 Bar... Yeah I think the reason I have a alot of knock is towing the trailer. I just pulled some timing in all of the cells that was showing KR so I should be ok for my towing tune. What commands the computer to go into Open loop? Does the engine need that extra fuel? or is 14.7 optimal?

[Road]

I don't see that pe is disabled but the only condition that is close to being meet when it goes rich is map and that is at 109 kpa the tune is set for @130 kpa. My only thought is the map linear is incorrect giving false map reading. What map sensor are you using?

[Mr. Smelly Gas]

Thats I what I meant when I said disabled 130KPA is almost 5lbs. of boost for me the Most I ever get while towing is 4 psig which is 126KPA Absolute, besides my TPS is not close to the 75% enable. I hardly ever get above 50% TPS.... I am using Bosch TMAP 2 BAR.... I think it is the IVT Gain table is causing me to go fat.... I checked the MAP linear per edelbrock it is correct.

[schpenxel]

Easy enough to check. Set the upper parts to 1, disable cat over temp protection and see what happens

[Mr. Smelly Gas]

Easy enough to check. Set the upper parts to 1, disable cat over temp protection and see what happens

When you say "upper parts", what exactly is the upper parts? lol sorry all this is new to me

also does it need the extra fuel? or is 14.7 Optimal?

[Mr. Smelly Gas]

Oh i get it...Upper parts = lower MAP numbers??

[Road]

Ivt are set to 1 in the uppers. Looks like 2.5 bar map linear too me

[Mr. Smelly Gas]

while towing my MAP is from 85kpa to 125 kpa. The left side of the table shows enrichment! So if change to "1" it should stay on 14.7? Unless I need to leave alone and let be fat, but I am hoping this will help fuel econ

[5FDP]

I wouldn't want to have 14.7 afr while in boost but that's just me, even your PE right now at 12.5ish in PE kinda scares me for a supercharged truck.

[Mr. Smelly Gas]

well i tried attach a pic of my spark plug but it wont load for some reason.... But my plug reading shows good fueling.. when I tuned it, it was in march, I didnt have any KR at WOT. I might wanna double check it in all this heat.... It was 102 here today. My IAT's are pretty high too...

[Mr. Smelly Gas]

Here is another log this time with my wideband.. Cant figure out why its going into open loop only when towing... I haven't seen it do it (besides PE WOT) when not towing... I mean it get down to 11:1 that is richer than the 12.5 command @ PE. Don't understand. Someone please help. denalitowing1.hpl

[schpenxel]

I still say disable cat over temp protection and see if that is what is causing it

Right now COT is set to max enrichment value of 1.1

Your commanded AFR is going to 13.3 (has some other values in different parts of the log but this is about the richest I saw)

14.6 stoich / 1.1 COT enrich = 13.27

That seems awfully suspicious how close that works out

Not that I think staying in closed loop in boost is a great idea... but that's what I would try next to do it if you're set on doing it.

[Mr. Smelly Gas]

Ok i will try that and see thanks

[Mr. Smelly Gas]

That done it... Stays at 14.7 until PE... I really didn't see that it helped much on my fuel economy. I might just go back

[schpenxel]

Good deal. I dunno how much fuel you'll really save.. guess it depends how often it goes into PE. Not sure it's worth the possible trouble