30003 Rich Issue
Hey there!
Picked up a 30003 to put on a bone stock crate 350 sbc. Basic settings cam at 1 and warm RPM at 700. Eth 0 (rec fuel) timing is +10 degrees.
This is running extremely rich, bellowing black smoke and backfiring. Seemed to run great when cold. The trim is +50 and AFR at 20 when idling.
I called FiTech and they said to adjust the IAC. Frankly, I don't understand how adjusting that is going to fix it running this rich but I tried anyways. Applied all zeroes to IAC and targeting between 3-10 steps. It's either on 0 or on 100, it will not go anywhere in between, going in increments of 1/16th of a turn. Eventually if you turn enough it will move, but then to get it back the other way it takes multiple turns to make any change, then it immediately raises RPM's when you get it in too far. But understand this thing is blowing out extreme amounts of black smoke making being around the car unbearable so trying to fine tune it is hard.
So again back to the rich issue, doesn't that need to be fixed first?
Car runs well with a carb, just thought it would be better with this EFI.
Just to provide a quick update on this.
After some playing was finally able to get the IAC set between 4-10 most of the time at idle. Car seems to be idling better now after adjusting IAC. However, it still has no power under load. The AFR is 20.6 and never changes. Idle, load, accelerating, decelerating, it never moves off 20.6 even though the target AFR target is always changing.
Hi, I have same problems with my new fitech 30003 installation, runnin rich and lots of hesitation under heavy accelation, but after I adjusting and syncronise both the front and rear butterflies, adjusting IAC and then reset all learning except IAC, after one hour test drive car running very good and no hesitation.
Quote from BDCFiTech on April 24, 2022, 5:02 pmJust to provide a quick update on this.
After some playing was finally able to get the IAC set between 4-10 most of the time at idle. Car seems to be idling better now after adjusting IAC. However, it still has no power under load. The AFR is 20.6 and never changes. Idle, load, accelerating, decelerating, it never moves off 20.6 even though the target AFR target is always changing.
On a 350 block, you may want to try Cam 2 settings as that is what I used on a few 350 crate motors I setup for a few people. Also it is critical to set-up IAC properly with adjusting the front and back butterflies so they are in sync and IAC set to between 3-10 @ 170 degrees coolant temp. Lastly what type of distributor are you using? A stock GM distributor works best with the 3003 Fitech. Fitech themselves recommend a stock GM HEI distributor. Too many aftermarket distributors are made in China now a days and quality is questionable.
Just a quick update on this. We received a new O2 sensor from Fitech and it seems to have fixed our issue. The AFR is now correctly changing based on input conditions. It's like a new car.
I'll double check the rear butterfly control, we only set the front.
Only complaint now is that under load while driving and punching it we get a bad squealing noise like a belt (it's not). Know if that can be tuned out?
Also, it is an HEI distributor. Plugs at 35 thou (was getting misfires at 45, so moved it back to 35).
I've also been having this issue, been driving me up the wall, afr will shoot up to 20.6. under acceleration throttle body sounds like it's trying to suck a goofball through a garden house under any acceleration. Bought a new 02 sensor after reading your post hoping this allows me to actually drive the car.
If you have made a lot of changes you may also want to try resetting to default under the write to EFI menu and choose v8 or whatever you have then start over. I also did this when the O2 was replaced but we hadn't made any changes beyond the initial setup stuff and idle AFR, so it was more for peace of mind.
It's interesting your AFR goes UP when you accelerate, it should go down because higher throttle input requires more fuel.
Your target AFR should go down under acceleration but your actual AFR goes up?
Keep in mind my AFR was basically locked and not changing even though the target AFR was changing which sounds different than your situation. Good luck though.
I worded that weird. Same exact scenario you have going on basically.
Quote from Dratka on May 3, 2022, 10:48 pmI worded that weird. Same exact scenario you have going on basically.
One other thing we did after putting in the new O2 and resetting the system to defaults, I also backed out the throttle screw all the way until the throttle blade stopped coming back, then gave it a quarter turn to open it up slightly and used that as my starting point. Then I did the initial setup, warmed up, and set IAC steps.
I've also noticed while setting IAC steps that you have to be willing to shut down the car and start it back up a few times while setting the IAC, then double checking, occasionally tapping the throttle. It helps and the car may idle differently than it did before shutting down even without making changes. They don't really spell that out in the instructions but it does seem to help. I read that on a mustang forum I think and it definitely helped me.
I also make sure after making a change, send to ECU immediately. Then before starting the car, turn ignition off and wait for PIDS on the dashboard screen to go out to know it saved.