Bucking, Hesitation, Stumble 7MGTE (Video)

7MGTE 9psi Gt35r turbo, external waste-gate, 550cc injectors, Walbro Pump, AFPR, Fuel Mods Etc...
Lexus AFM with extra long screw.

Hey, I am having an issue, my supra is cutting out during acceleration even when I do not release the gas pedal, it cuts out during acceleration. Any advice? What could this be?

Is this bucking fuel cut? It will not go passed 4k rpm when I floor it WOT. Why am I still hitting fuel cut? Which piggyback should I use to prevent fuel cut? I am running very rich, and still hitting fuel cut with a extra long screw in the Lexus AFM. my fuel pressure is around 42 PSI. If I lightly feather the throttle it will go above 4K rpm, if I put the pedal to the floor WOT, it will not exceed 4K rpms. When I floor it, it cuts out... In the video, when it is bucking, I am not releasing the gas pedal, it is cutting out under light boost.

I had it leak tested, there are NO boost leaks. Nobody can help me, it cannot be that hard!

Please help!
http://www.youtube.com/watch?v=RFW3-wl939A*
http://www.youtube.com/watch?v=kj0AVML3zzY
http://www.youtube.com/watch?v=yzFxlrjIZrA

Listen to the difference!!! (my buddy's supra)
http://www.youtube.com/watch?v=Ka1lFqkVh1o
 

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Zrain25;1959914 said:
Let ur car reach operating temp before doing that shit. Unless ur temp gauge is broken.
How much boost do u hit when it bucks

I hit 9 PSI Boost, 40 PSI Fuel Pressure, 550cc injectors. I turned the fuel pressure down to 29 PSI and it idles at 600rpms, so it brought the idle down, and smooth. Here is another video of what it is doing when my car is warmed up.
http://www.youtube.com/watch?v=RFW3-wl939A

I got again Code 34
I have the Atmosphere HKS SSQV BOV and MBC + Ext. Wastegate. Is there an adjuster screw for the BOV that is letting out too much air possibly while I am boosting?

Thinking aloud. Why am I hitting FUEL CUT with the Lexus AFM, Walbro Fuel Pump, RC 550CC injectors, AFPR 29PSI, and the Stock ECU? The KVAFM upgrade should have prevented fuel cut; however, in this case, it did not. Which Piggy back computer do I need for the ECU to stop hitting fuel cut if this is the case? I have come to a conclusion, I strongly no longer suggest taking into consideration the modification of downgrading to a LEXUS AFM and 550's, because I am still hitting fuel cut with previously listed fuel and air modifications which were suggested broadly by those communicating within the forums.

My car was operating at warm temperatures during the video.
(The stock Temperature Gauge in the video is not hooked up, I have an aftermarket Temperature Gauge in the 3-row-Gauge-Pillar)


Zrain25;1959915 said:
Nice color supra btw I got the same color

Thank you I appreciate it, if I ever get my Supra running correctly again, maybe I will look into respraying the car Midnight Blue w/ Xtra Clear.

Overall, I am going to invest in an HKS fuel cut defender and moniter my A/F Ratio's since I am running rich anyways. I am sick of hitting boost cut because the ECU wont allow me to increase above 12 psi, let alone on a stock turbo. With my upgraded turbo, I am going to need a Hks FCD unless you can suggest a better tuning device. I wanted to try MAFT pro, but it prolly is not necessary with the lexus afm and 550s
 
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