Hits fuel spike at 3,500 rpms Help!

Truck runs good until you get to 3,500 rpms then gets stuck, afr's peg out meaning its dumping fuel, ive replaced maf, B1 S1 o2 sensor, TPS.

I think it maybe a short in the wiring, or bad coolant temp sensor, or just dirty intake.

Wondering if anyone else has had this problem?

 

When was your last fuel filter change??

Your numbers are telling you it is being asked to dump fuel but it is not really happening .

Might be the pump is getting tired or filter maybe kinked crushed fuel line.

I am on my first sips of Coffee I might not be awake yet

 

Fuel filter is clean and fuel lines are fine, just installed a new 255lph pump two weeks ago. Its something to to with the fuel mixture, like the ecu is giving it to much fuel when it reads full throttle because i can ease into it and it wont do it

 

First question, is the truck properly tuned. Since you're running 255lph pump on E85, can I assume you're turbo? Boost spike? Incapable MAF for the amount of boost? I don't know much about 2RZ, but possible the MAP not able to handle the psi you're running if it have one?

When engine peg, what's the afr?

 

I love your disclaimer!

 

When it spikes it maxes out the afr gauge
So 9+
Dont have turbo, just e85

 

I would assume you have a piggy back, is it tuned? Stock size cc injector or....

 

They're the 330cc pink 2.7 2tr injectors
And no stock ecu but i need a micro squirt

 

What about afr before 3500? Bogs @ 3500, will it rev past that? What about during idling and revving?

 

OP, you might want to consider posting this issue under "performance and tuning" section

 

700-3200 goes from 14.6 to 13.4 then 12.2 then at 3,200 it goes to 10, at 3,500 it maxes the gauge out but then at 4,000 it goes to 11 and stays there until 5,900

 

I am assuming that you are talking about a mpg reading off some sort of a scanner. Those number are a calculated number based on air flow reading from the MAF. I wouldnt pay that close attention to them. Your fuel system uses a pressure regulator with return line to the fuel tank and unless there is a flow meter in both the inlet and return you have no way of knowing with accuracy what your fuel consumption is.

 

No i i have a actual AEM w
band o2 sensor, and gauge

I also have a fuel pressure regulator to adjust it and i have it turned all the way down, anything over 23psi of fuel pressure it won't even go, it will just dump loads of fuel

But i had an extra intake manifold so i ported it and im going to clean my injectors out

 

I unplugged the secondary o2 sensor and it made a huge horsepower and torque difference but still does the same thing

 

Have you try reusing orginal injector? Only thing I can think of is the duty cycle of the 330cc injector at 3500rpm.

 

Your probably right but the OEs are 285cc which for my application is way to small and they're two hole, so it doesn't mix the fuel well and pings