so ive rebuilt the motor (basic built bottom end), have bout 1200 miles, now i put the waste gate back on, ran fine, gave a little boost and it was great.. then during a small pull the car shuts off..i restart, my AFR is 10..its stumbling and angry.. i check under hood, and hear a hiss, sure enough the dam missing link's filter had blown out, so i get a cig filter and patch up.. start car, and its really still not happy, vac is -18, but AFR IN 10-11.5 @ IDLE...so i let it sit over night. start up, seems to idle fine, but afr is still rich like 12-13...it eventually cycles to 14.7 area.. then goes lean, stumbles (vac gets pulled to like -15) then revs it self back to 14.7 and all seems fine.. idk WTF.. ALSO now when i shift, instead of going lean and coming back to 14.7, it goes rich, like 12.5-13, then lean and then to 14.7.. any ideas=? some times as i am in N, coming to a light RPM sweep 1200-1500 , during AFR is bounces 14-17 then settles..

*ive checked for vac leaks, could not find any
*IAC and TPS checks out
*plugs are new, ngk br7 gaped to .40 (i know not ideal for boost, but i wasn't boosting during the break in)
*NO evap shit or EGR stuff to burn wires on
*only cel's is 31, 32...had those awhile lol
* MP 60mm, cleaned thoroughly like a month ago, and the gasket is coated with the copper spray
* 96, 255 pump, hahn PF, idle pres 49 psi ( this doesnt change during symptoms)
*before issues idle was 1K-950 ~-18/-19 in Hg
* while crusing ( not boosting anymore till this is fixed) it seems to run ok.. 13.8-15.2 AFR, just when i shift it goes rich then lean (17+) then to 14.7 area

thanx for the help guys...

I think maybe portfueler module took a shit. Pull power to the portfueler module and drive it (without boosting of course) and see what happens. Let us know.

Get rid of missing link also. I would go with FCD. Easier and hassle free.

I dont know why i didn't say this before in the last 2, but i think the portfueler is adding fuel sometimes even when you are not boosting. Is everything as far as fuel and ignition stock? (such as )

ive been driving without boost, it seems to add a little fuel when i shift, instead of lean it richens up for a sec, then leans out, and when i compression brake, it grumbles (usual, and then i get a POP about every 3 sec... im thinking a leaky injector since it drives fine,..if i sit (idle) then roll out in N, some times it just dies, i see it pull vac to like 15 and die..

fuel is no stock fpr, aeromotive @ 49psi, walbro 255, i just swapped out coil packs today to see if that helped, and it didnt. (MSD pack and wires)

hmm.... The fuel pressure hahn recommends is 45psi on that aeromotive. Not really a big difference but just for shits and giggles try 45 anyway if you have time to mess around. If not, no biggy. Umm.... you may be right about an injector being stuck open. You should get a multimeter and check resistance of the primary injectors to make sure they're within spec with your chiltons/haynes manual. If so, I really would pull power off the portfueler and see how it drives. Keep me/us posted. Hopefully we can get this figured out asap so you can start boostin!!! lol
Cameron

i still havent pulled power yet, but ive pulled plugs, they dont seem wet, so idk.. reset ecu let idle for 10min (idles fine), then i see it pull vac to -15 and go lean stumble and regain.. i let it idle some more, it does this a few times.. then take ebrake off, and coast out of driveway, and as soon as i do and apply break.. fucker dies.. restarts fine..now its startin to do this at a few lights too.. lame.. took ML out, still same shit..

cel 31, 32 still (egr and evap..removed)

hmmm.... guess all you can do is check injectors and pull PF power. I dont know why other people that know more than me aren't getting in here. I'm nowhere near the most knowledgeable, just trying to help some, if any.

have replace fuel filter (though tit may need it) and the AIT, still same issue. is it possible that when i blew my Ml filter and she ran rich, that it fubard my upstream O2 a little?

Doubt it, oxygen sensors are fairly robust. Unless it was already on its last leg.

I would not waste money replacing parts unless they are diagnosed to be defective.

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2012 2500HD LML

yea, which sux, b/c im not sure what else there is that could be causing this.. every time, esp 1st, if i go a lil then shift to N, it richens way up, then leans it self out where its supposed to be,.. and it doesn't make sense, when i let warm up and idle for like 10 min, when i roll out in N that it wants to die...

on your fuel maps what are the values on the negative manifold pressure side? Are they all set at zero?

they start adding fuel @ 0psi, anything below is 0

ok, well thats right then. i dont know what to tell you man

i think either 1 of my injectors has a slight stick, or when i ran rich /safe mode, it fuckzored my WB sensors accuracy

possibly. All you can do is check

yea theyve been sent out for cleaning lol. so crossing my fingers if thats not it then its gotta be my WB