Running Pig Rich Under Boost/Hesitation/Fluttering

[HolyShiznit]

Well plug readings and wideband don't lie, car is just running stupid rich in boost. I have already checked my intercooler piping/couplers for leaks and there are none. I am running a JWT ecu setup for Z32 MAF, 52# injectors, and 14.7psi/1 bar. The engine has about 1k miles on it since being rebuilt after it ran lean and I popped three pistons. Only things that were changed was I removed the butterfly valves and swapped heads (ported and polished). I also have a Tial 38mm external wastegate that has the 1 bar spring in it.

It has trouble maintaining freeway speeds, it starts ....fluttering is the only word I can describe it and stumbles then I let off. The boost rises to .4-.6 bar then flutters, if I let off and slam throttle 100% back down then it pulls through, but runs stupid rich. Around town it is normal but mid throttle/spooling it sometimes does the fluttering, stumbling thing too. I am at a complete loss. It also seems to be running lean/high EGT's before boost. Fuel Pressure is fine and the fuel pump is in good working order, the MAF is fine too (I checked voltage and even switched my spare out just in case). I am running a draw through open atmosphere Greddy Type-S bov but I dunno if that could be the problem. I normally don't ask people questions on these forums but I am at a loss and could really use some help from guys with more experience than me.

[HolyShiznit]

Well I fixed the weird hesitation/boost flutter crap problem but I am still running stupid rich under boost, my PLX goes from 14-13:1 and then I nail the throttle and it goes 12-11-10 "RICH". I have no clue as to why it's being such a pain in the ***. Could the JWT ecu been damaged or something? At this point I am at a complete loss. I haven't checked my stock 02 sensor yet, but I don't know why it would be going so rich if that was malfunctioning. Anyone got anymore ideas?

BTW: I solved the BOV situation by recirculating it. Now I still have the fuel problem.

Could something have happened to the JWT ecu, while I was tearing the car apart? Or could I have just gotten a bad tune, I dunno what else to check.

[Structure240sx]

really does sound like a boost leak.

i think a few post got deleted in this thread so im not sure if you checked for that or not.

[HolyShiznit]

Well I was fiddling around with everything and playing with the SAFC II to try to take out the fuel, then I went and checked the ECU. Hey look! 50lb injector tune, wait, I have 52lb injectors.......thanks JWT. I am now 100% certain this is the problem, go me.

[klattr1]

ive never seen 52lb MSD injectors though. strange.but if your car is running in the 10:1-12:1 range, thats typical for Jim Wolf ecus (not always though haha). if your settings on your SAFC are zeroed out, then leave it and then buy ad adjustable fuel pressure regulator and lower it some and then retest it with your PLX if thats what u want to do.dont get out of the safe range though!

[Structure240sx]

are you able to lean it out with the safc?

[HolyShiznit]

I am able to lean out low throttle settings, I drove around last night and couldn't lean it out in boost, and I am running richer than 10:1 because the PLX can't read lower than 1o:1, it just says, "RICH" on the display. Grrr... I am idling at 12.2:1, and I know that is way too rich for idle.

[Structure240sx]

yea i have the same wideband

so no matter how much fuel you take out on the high throttle map it still read rich? do you have the in/out settings right on the safc? and have you checked and double checked for boost leaks?