When I'm at low-speed, low-RPM and floor the gas pedal for a bit and let off, sometimes the car backfires. If it shoots out a fireball, then that's cool.. but I have no idea, so...

Would this be tune related? A leaking injector, maybe? Evo IX tuned on FlexFuel, 1050 injectors, Walbro 255. My tuned is locked, so no way to see what's going on there. I don't want to bother my tuner unless I can confirm it's the tune.

 

Has it always done it? Or is it new?

 

I don't drive the car much.. so memory is fuzzy. I've been on e85 for a long time and don't think it did it then, but now I'm on pump gas and it is. So, that should mean tune? Unless the injectors somehow were affected negatively while sitting/occasionally driving with e85. I guess I need to put e85 in it again and double check if it still happens.
I know FF is just a bunch of interpolation between values....so maybe it's just a "glitch" in the system...?

 

If you're below E20ish and above E70ish the tune is operating 100% on the pump gas or E85 maps respectively.

But it sounds like a slight tune different is likely what's causing it. Likely the decel fuel cut needs tweaked.

Unless there's other drivability or AFR issues I wouldn't think it's the injectors or something mechanical.

 

I think the car is right around 30% now, so I'll run it out and put some more pump gas in. The car bucks under low RPM while driving through parking lots. That's annoying, but it's done that since the first day I've ever had the car tuned, with any tune, any tuner. I've just gotten used to it. I'll talk to my tuner and have him look it up. I have noticed the car seems on the rich side when I change gears.

 

snapple crack pop toon bro.

Almost every single modified car here in NY/NJ has that annoying douchy crap on it.

 

its worse in NYC...Can't stand that ****.

 

Indeed, and it echos off the buildings which makes it even more *** hatty.

 

LOL maybe Jay snuck that in

 

Maybe stop doing that.

Problem solved.