Anyone have any ideas?

 

Need to get a wide band o2 in there sounds like the fuel system is riching up mass an then leaning out so then ecu trying to compensate an the vafc is waking it out.Get an new ecu an get it tuned....From experience you need good fuel management an spark control :P

 

I got an idea cuase mine is doing that right now the set up goes as:::: d16z6, jdm dizzy, garret t2/t28 hybrid .42/.60 trims, volvo blow off valve 450cc injects, fmu , and boosting at 14, lbs(built z6 motor) that is why the boost is high , the only problem i have is the bucking at idle until about 3000 rpm or at hard acceleration it is ok the cold start up is what really kills me the only thing i had found so far is that one of the injectors is leaking down
my resistors are wired in right and the timing is right and IGN,,, is good only thing i think is the injectors are too big im still seeking and needing help like you .....

 

OK I checked the cel codes and the only one I am getting is number 3 MAP - manifold absolute pressure sensor So what does that mean and what do I do about it? Thanks

 

Go back and make absolutely sure you've got the AFC wired up correctly and everything is tight. I had the same problem at one time and traced it back to 2 reversed wires on the AFC harness. Whoops...

 

There was a guy around town who had a leaky injector... it blew up his engine in about 80 miles because he never fixed it. I didn't think FMU were too good for that high of boost?

 

Make sure it's still hooked up (ha ha)... I thought a MAP cel was indicative of boosting over 12 lbs? Either that or your map sensor is screwed. I'd go back and check everything from the ground up with a fine tooth comb. Check your wiring. Check you AFC. Look for any loose or missing wires and post the rest of your setup. Check your VAFC settings too.