gillysmi

I removed the front top cover from my intercooler. watching my afr after that and it is now around 13.5-14 to a little over 14. prior to that it was 14.5-15.0. am I running to lean now. I didn't think that would have an effect on it but it is definitely running leaner than it was.


it may just be me but my truck feels a little crisper now as well. put about 250 miles since I took the front cover off.


any thoughts?

11FX4EBOOST

Not sure how accurate the gauge is that is being used, but stoichiometric afr is 14.7:1... if gauge is accurate then Id say you are a little rich now and were bang on before.

gillysmi

I am using the torque pro app. so I am not sure how accurate that is. but it is definitely different that it was. I will try to keep monitoring it and see what happens.

Z7What

Higher number is lean, lower number is rich.

Wayne

Wannafbody

Rich is safer, lean might make a bit more power.

Z7What

Although that is partially true. To Rich can wash rings and to lean can mean very bad things.

Not sure what the Ecos run @ WOT but in the Lightning world around 11.4-11.8 @ WOT is what you want for street tunes. 14.7 while idling or not under load.

Wayne

Al Kohalic

This is with my bone stock company truck that averages 19 mpg each tank. This screen shot was taken while traveling 70mph. At normal cruising speed, my A/F will bounce between 14.4-15 constantly.

JCP281

At cruising speeds (meaning part throttle) your should be somewhere around 14.7, which is Stoich. Your not going to be perfectly at 14.7 100% of the time, but you should bounce around it. If you are in the mid 13s while just cruising, you need to get that fixed, your dumping extra fuel into the motor. Your computer should be able to compensate for most changes that occur. Since you removed the top cover of your intercooler, did you unhook the battery?

If not, I would unhook the battery for about 10 min to reset the KAM. The KAM or Keep Alive Memory, is Fords way of the computer remembering the setting to make the car run. Disconnect the negative battery terminal and pull the headlight switch on. Let it sit for 10-20 min, then connect it back up and turn the truck on. Let it idle for a little bit with the a/c lights and everything off. Don't touch the gas pedal or anything else, just let it sit and idle. It might be a little rough for a few minutes until it relearns the parameters, then it should be good to go.

See if that helps.

cshiznitzj

additional note to add is although 14.7 a/f is stoich for gas, E10 is closer to 14.1 a/f stoich. log lambda, the percentage of stoich because there can be vriations of blend you get at the pump.

gillysmi

really good info guys. thanks a lot. the last 4-5 tanks have been E10 unfortunately regular is hard to come by.