rb20det help !!!!!! please

[DAMRB20S13]

ok i bought a rb20det an swaped it into a 240sx s13 .. im having problems.. its all swaped in runs good in park... but when i try to drive it it starts choking an spudering . it spools up 7\8 psi an holds it an it moving like 15mph thats it , very slowly like the maf is messed up so i cleaned it an still the same ,i can rev though it very slowly in gear but if i try to go faster it stalls and chokes ? , car dies when i unplug maf like it works ..all wiring is well done .. i can stand over the car an rev the piss out of it and it blows off like its all good (IN NUTROL) its got a walbro - front mount and afthermarket bov, thats it the rest is stock... ???????? iv been working on this for a while now and im clueless..

thanks for helping much apreciated keeping nissan alive ...

[stunnaben]

Sounds like it is running in limp mode honestly..... Won't rev over what 3k?

[DAMRB20S13]

it runs idles smooth . i can rev it all i want in nutrol or not in gear but in gear under a load it bogs an just spools up the turbo it hold 8 psi . i can drive it but very slow or at low rpms it wont get up an go . its like some thing is holding it back from reving out ...its like as soon as it see's boost it lags an bogs .so i back out of it an rev it slowly in gear and as long as i dont spool up the turbo . it was running rich for a while like it had a stuck injector but the more i ran it the clear it got . it used to puff black smoke while just running in nutrol , now its clear and some times i think it puffs black smoke when i try to test drive the car ..... its hella weird ... it runs fine in nutrol go ahead play with the trottle lots of power just not in gear ? could the timming be off i didnt move it. it was bolted in spot by factory it looks like it was never moved but then again it don idle below 1500 i tryed turning the cas to idle it lower sounded better but still the same old boging.....

[Sileighty_85]

Check for Vac/ Boost leaks

[stunnaben]

first of all it's neutral, and timing

I'd look into boost leaks like he said, your maf may be reading a shit ton of air and then it's only getting 8 psi so it's loads your engine full of fuel, bogging it down. Does it run fine when not in boost?

[DAMRB20S13]

but it hold 8 psi like it sould if it had a boost leak it would be less ... or what is the stock boost on a rb20 8 or 10 ? still it hold boost in the intake system when i drive the car i see the gauge at 8 psi i hear the turbo but it sounds like it boging until i let of the trootle and it blows off .... its a brand new swap straight from venus in sac rite out the crate had 250 plus compression in each cylender dry.... all fluids in car are toped off no leaks .. ill check for boost leaks tommrw

thanks guys