Will increasing fuel pressure affect the LTFT on my car, or can it compensate for it and adjust itself? I'm running lean at WOT and need to increase my fuel pressure because of it. I have an '89 with a MAF system.
My current readings are 116, which I think is a little rich.
Re: Is LTFT (Block Learn) affected by fuel pressure? (shotchkiss)
By your mods-cam etc...have you had a prom programmed?
108 is as far as the stock program can compensate-so you're already getting close. If you raise the fp you may well richin it enough to hit blm of 108.
Why do you say it's lean at wot? Have you put it on a wide band? Or off the O2 mv? What size inj?
Still have the stock chip. I was hoping the car could compensate for the changes I made. My WOT readings I took off the O2 sensor, they are in the low 800 to high 700 range, which I thought was too low. I'll try another O2 sensor just to be sure, they are pretty cheap and my car car only has one. I think it is still the original one anyway. I am still using the stock injectors, I think they are like 22lb ones?
Sounds like it would be worth a custom prom about now....and it would be well worth it to check it at wot with a wide band. The narrow band is a real ballpark only. If you lived closer-I'd offer my wideband....oh well.
If the O2 sensor voltage at closed loop is rapidly toggling back and forth rich/lean, then it's working.
Since you already have the ability to datalog, yup, he'll be able to nail it. If it's still off a bit, he's been great about retunes to finish dialing it in. It would still help him out a lot for wot if you could get a run or two on a wide band though..
Maybe have him tune the part throttle first-then spend a bit on a dyno pull with wide band....
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Is LTFT (Block Learn) affected by fuel pressure?
