tbiggybig

So under normal idle i have an afr of 14 under load i have 13-15 at half throttle anything past half throttle is where problems begin it spikes to 20 and then cuts back to 13 and sputters wont let me accel until rpms come back down to 3k and afr goes back to normal am i running lean or rich and what can be causeing this are my coils not keeling up fuel delivery problem tune problem? Its all stock atm ive been debating doing a turbo but i want to get this problem under wraps first. Any ideas anyone?

tbiggybig

Sometimes if i pull my maf sensor and clean it it stops usually but i did it about 3000 mi ago so not sure if its that it happens every once and a while on hot days usually or days of long runs. It will also backfire and make popping noises during the rpm drop and sometimes stall

Legot

iTrader: (1)

It's either you're ignition failing (coils, plugs, and wires) or a fuel delivery problem.

What are you using to track your AFRs? You'll be able to better pinpoint the issue if you can log Commanded AFR, Actual AFR, Engine Load, and Throttle Position. If you can't do that then just go with targeting the fuel pump and ignition. They're both pretty common failure points.

tbiggybig

I used the torque obd2 app on my phone and i think i can log them all just need to set it up ill collect some data later

tbiggybig

I took a video and a few screen shots of the data log ill post the video here as soon as i upload it but heres screenshots in the mean time

tbiggybig

Heres the screen recording of the log did the best i could to explain whats going on when i refer to throttle im refering to pedal position once again problem only occurs when i push the accelerator past 50%

https://youtu.be/m8ja-XWUolw

Legot

iTrader: (1)

Yeah, definitely start with replacing your fuel pump, then reset the memories using the 20 brake stomp and disconnecting the battery for a while.

That should get you good to go.

tbiggybig

You guys dont think its coils? And before i dive into this could it be anything else any ways of testing fuel system?

Legot

iTrader: (1)

Coils can't cause lean spikes.

tbiggybig

Replaced pump and now its running wayy better it leans out to 20 when i pull my foot off the pedal now not sure if its something i should be concerned about but besides that under load it runs a little rich 11-13... but acts like a new car now responds better... must of had this problem since i got it.
Also the new pump wasnt sealed in a caseing the filters were exposed maybe thats the different design everyone was talking about? But i threw it in there as is the line from the sender unit was a pain to put on... had to nearly pull the assembly apart to get it on.

Legot

iTrader: (1)

It's supposed to do that, fuel is cut for efficiency in overrun. That's why it's more fuel efficient to coast in gear rather than in neutral.

Consider resetting your NVRAM and KAM so that the ECU has an easier time learning new fuel trims.

tbiggybig

Cool thanks ill give it a shot i drove it a bit more today and it seemed very different before it was very torqueish jolted everywhere now its way smoother kinda feels sluggish in a way ill give that a shot see what happens.