Throttle cut and loss of power
Hey everyone,
new to the forum but i wanted to post a log in here because i am currently battling an issue with my fitech. The motor is a sbf 302 trickflow heads and a mild isky cam. I am running the 30004 system. Car vacuum reading is between 8 and 9 at idle. Also has brand new o2 sensor.
after installing the system the car pulled hard this was with cam setting 2. I them switch it to 3 because of my vacuum reading and didnt notice much of a difference initially. I then notice one drive that anytime the car was under load and accelerating it would cut throttle and start to bog down/almost act like a misfire. Would cam setting 3 really cause this?
i have attached a snippet of a log where the issue happens. Car will be under load and hard acceleration and completely fall flat on its face. The weird thing is if you bring the throttle back slightly it will pick up and then if you mash it falls right back on its face. Almost like a safety cuttoff.
is a log during idle more useful?
i had posted this in the wrong section acouple days ago and wanted to get this in the correct section.
On lines 21 thru about 32 the afr drops a lot ( around 20) at mostly wide open throttle . It leans way out. I'm not good enough to tell you how to fix this but the WOT settings should fix this.
I would say that if it was running fine on cam setting "2" - revert back to that setting & have the FITech re-learn. There is a setting somewhere that allows you to clear the learned settings.
A important thing we dont know. What kind of distributor are you using and are you using the Fitech to control timing? By your log file your afr goes to 20 which is a lean condition and the afr trim is at 50. AFR Trim is important as in the lean case it has reach 50 which if I remember right, the learning system has max out on fuel added and the car needs more gas which the learning cant provide. Cam 3 setting is correct for your vacuum reading, but a 8 or 9 reading on a small 302 block seems very low. Probably due to your heads or type of cam. If you change the cam setting from 2 to 3, you need to reset the learn. Too many engine upgrades such a heads, cam, distributor, generally dont work well easily with these " works out of the box FI systems". Most cases require a custom tune file which require someone who is very experience in doing so. You are almost better off with a carb.
Soda Pop I couldn’t disagree with you more.
Quote from Austin DeHaas on November 19, 2022, 7:55 amSoda Pop I couldn’t disagree with you more.
On what point?
I wanted to update this thread.
I hooked up a fuel pressure gauge and noticed that under acceleration the fuel pressure drops from 58psi at idle to 20psi at acceleration.
I replaced the fuel filter prior to the fuel inlet and still have this issue. I forgot to mention that at one point I had put a vacuum plug on the vacuum port of the regulator. Could this have damaged the regulator?
could all this just be due to a bad pressure regulator?
Thanks
Would love to hear an update on this. I’m having the same issue, I have a new fuel pressure regulator coming but I’d love to hear if you found a different solution.