Lean spikes after dyno

[C6maniac]

So let me start by saying the tune on the car was perfect and the car was driving smooth as stock prior to the Dyno. Made a few pulls and when I pulled out of the dyno onto the street, it was bucking like a mule. AF would spike 20:1+ as this happened and it?s only under light load. Give it moderate throttle and it gets better. WOT feels perfect but was going a little leaner than where we started. Been going back and forth with my tuner and can?t get this figured out. Will do same thing with MAF turned off as well. New plugs, coils, wires and injectors flow tested. Smoke tested intake, exhaust and crankcase. 200psi across all cylinders. Any help appreciated.

[Sub8]

So let me start by saying the tune on the car was perfect and the car was driving smooth as stock prior to the Dyno. Made a few pulls and when I pulled out of the dyno onto the street, it was bucking like a mule. AF would spike 20:1+ as this happened and it?s only under light load. Give it moderate throttle and it gets better. WOT feels perfect but was going a little leaner than where we started. Been going back and forth with my tuner and can?t get this figured out. Will do same thing with MAF turned off as well. New plugs, coils, wires and injectors flow tested. Smoke tested intake, exhaust and crankcase. 200psi across all cylinders. Any help appreciated.

Airleak after maf. Pipe off or slightly off

[C6maniac]

I smoke tested the whole intake side, no leaks.

[Tfoggy]

Weak or erratic fuel pump/ or fuel pressure regulator .. Check "real" pressures at diff driving conditions. ???

[Alvin]

Can you get a log? It's likely something simple.

[C6maniac]

Weak or erratic fuel pump/ or fuel pressure regulator .. Check "real" pressures at diff driving conditions. ???

Yeah that?s what I?m checking next.

[C6maniac]

I have plenty of logs. I?ll upload some when I get home tonight. I have a very skilled remote tuner. Like I said though, it was perfect til after making some dyno pulls so don?t see it being in the tune. Even with fuel trims off or switching to SD, acts the same.

[C6maniac]

Can you get a log? It's likely something simple.

Not very computer savvy. Can't figure out how to attach a log from my email logs. Do I have to do it off the laptop I use for tuning?

[mememe123]

It could be your PE TPS settings are pretty low, and it only got tuned for PE or "higher throttle" from ~1k to ~3200k rpm?
Just download/save your log, and attach it in the message how you would attach an image, or anything else.

[C6maniac]

It could be your PE TPS settings are pretty low, and it only got tuned for PE or "higher throttle" from ~1k to ~3200k rpm?
Just download/save your log, and attach it in the message how you would attach an image, or anything else.

Will do tonight thanks