Rb20det running uber rich sputter when not in boost!!!

[S13goodness]

So I recently swapped a silver top rb20 so far I've only actually had it on the road a couple times but it seems like it's getting too much fuel lots of popping in exhaust an smells like fuel an previous plugs were black but I'll run it up to op temp an cut it off an then try to turn it back on an it jus turns an turns also hunts for idel a little but over all sounds good coils fire have spark no leaks just stumped on where to go from here?


But my ? Is is my fuel pump over taking my stock fpr I read somewhere Mabey on here that an aftermarket one is best but some ppl say stock one should be ok



Mods: fmic
Isis 255 fuel pump
300zx maf
Wiring specialties harness

[S13goodness]

Going to post video tomorrow

[xracerx972]

what are you using to compensate for your 300zx maf?

Assuming you've got some sort of fuel corrector, I would start with vacuum leaks and mechanical timing. Keep in mind that if your CAS key is broken, it is possible to have the CAS incorrectly timed as well.

[S13goodness]

Yeah I semi checked for vac leaks jus with carb spray nothing really happened need to make a boost leak detector at some point but my cas key is not broken thank god lol

But can anyone answer the ? I had about my upgraded fuel pump being to much for my stock fpr to handle? Idk I saw it somewhere Mabey on here or another forum that it can make it run a bit rich

Also the specailties harness I got had a newer style maf plug so I used the stock rb pig tail but have no clue what the pinouts are for that harness I'm hoping it's jus the maf cuz when I unplug it the cars almost dies but stays on?...

I'm trying to get this video uploaded but it's taking forever if anyone has any other directions to go all comments are really apreciated not my first swap but I'm stumped guys

[nicostarz]

S13goodness, i am an owner of a R33 sedan 40th anni, came with a crap 20e but i upgraded to 20det same silvertop as yours, i was facing this issue for several months day after day sputtering only when entering boost, this made me feel as if i was a rich man who was impotent, ive check coils, fuel pressure, fpr, fuel hoses, intake hoses, clamps, plugs, boost leak, maf, maf, maf, maf, boost leak, plugs, o2 sensor, wiring, boost gauge hose, intercooler (stock side mount) and found nothing until 2 days ago. my issue was sputtering while engaging boost, and though i have no a/f m, my friend with a nissan lucino (sr20 neo) told me "dude, you realize you burning rich?" he caught fumes from my engines exhaust pipe and smelled, he said it was richer than bill gates. at that moment i thought, s*** i know the problem now, i figured it was my o2 sensor or the wires gone bad, lo and behold i was wrong again. but i did fix the crystallized connectors on everything i checked and fixed my random shutoff problem(this was due to dry joints in mafs and required careful soldering to fix and re seal with silicone) with this sputter cause seeking adventure. now i dont know if this is your issue or the many out there, because i trolled high and low on google and joined countless forums in seeking an answer, i found none, but i did find some info that did help, my tps was adjusted to read 0.48 volts, as i heard on other forums anywhere between 0.45-0.5 is good. it seems this was not so, i heard when my friend said i was burning richer than bill gates so i retarded the tps to 0.47, in an instance i noticed the sputtering level has fallen, the next day i lowered it down to 0.46 and even less sputtering, and today i lowered it to .45 and to my surprise the sputter is something i am trying hard to hear, or get out of my engine when in boost.
so what happened was my tps was flooding the a/f mixture and i had to fully advanced my cas to run with less sputter. now im in the process of retarding both the tps and cas to correct levels a step at a time. big ups to Vermanucci who helped me with the timing light and discovering the root to my problem, i hope this helps the many rb20dets out there with the same issues, i am somehow glad it happened as i took a long journey learning the ins and outs of my rb20det, and fixed many problems along the way, now my engine is running good and getting back good mpg i am happy and shall take on a new adventure, time to install rear sway bar!!!!!! and do some body work to look good!!!!!!!! this is my daily driver also, so i barely get the time to work on it. My name is Nico and i hope this helps someone.

https://www.facebook.com/18858442784089 ... =3&theater this is my skyline. and my brother's skyline beside it.