91 240sx w/sr20det redtop BUILT Motor problems..

[ChrisCheezer]

Hello everyone, I'm looking for some outside opinions to a on going problem i have been having. that is keeping me from driving the car.heres what im working with

redtop sr20detHEAD:engine harness (new)HKS hgHKS cams 264 272arp studsgreddy springsgreddy rasport and mild polish3 angle valve jobcustom valvesnismo 555cc injectors, usednismo fpr, usedz32 maf (4 different ones all the same effect)gti-r turbonew temp sensor

Bottom end:BRAND NEW EVERYTHING (besides crank)ALL OEM parts.

management: ROM tunedfresh ECU (off a swap) ecu has no dio light (odd no?)

nothing is half assed, i tryred to do everything PERFECTLY.the car drove fine for the first 10 miles.

heres my problem i hope someone can shed some light on the subject

Key on ... no fuel pump sound...start: car starts up right away, and runs idle a/f at 15.0, for the first 10sec.(feels like a misfre) and then the motor just gets PIG rich, 10.0 with in the next 30 sec. fuel pressure is 42 when car is RUNNINGcar sounds like it has a misfire.. idle bouncing, FUEL dumping hardcore out the tailpipe. motor revs up fine, seems powerful and fast reving.

i pull the Rom tune off the ECU and the pump doesnt come on with the KEY, ON. car is put in "failsafe mode" The car seems to run a little better not dumping fuel as much and A/F is around 10.5 still sounds like a misfire, car will rev. normaly

pulled plugs: every single one looks the same, DRY, but fouled out BAD.re did the CAS and put the motor in time. same.. problems..motor compression is 150 ish acrossi have been through a million plugs, maf's, coilpacks, CAS,anyone have any thoughts?i have an idea what it could be, i wana see if anyone thinks the same thing. before i waste anymore money...

cant be a MAF cuz i tryed 4 known working ones, and checked my MAF wiring 10 time its perfect.

Cya,Chris

[driftin_sr20det]

Alright, have you checked all wiring. I mean really check it, check voltages, all grounds, check the continuity of all the wires from the ecm harness back to the plugs. I think there might be a wiring issue, or the ecu. If you have your stock injectors, maf, and ecu. I would swap them back in to see if the problem persists, if it does then you should be able to find the problem relatively easily. If problems end I would say its probably the ecu.

[SpeedRacer1]

O2 sensor issues?

[GTS4-R]

no id say its the tune....i had the same problem when i 1st tried running emanage with my new turbo....it would run barely and then it would lean out and die for no reason....we tried everything.....new maps, checked wirting a millions times....etc etc....then i fianlly sold the emanage, got an enthalpy tune and safc....and it runs GREAT

[White Comet]

no id say its the tune....i had the same problem when i 1st tried running emanage with my new turbo....it would run barely and then it would lean out and die for no reason....we tried everything.....new maps, checked wirting a millions times....etc etc....then i fianlly sold the emanage, got an enthalpy tune and safc....and it runs GREAT

this is my guess too but i have no experience w/ it

[ChrisCheezer]

i have checked everything, i forgot to mention that i drove the car for one day it ran fine... then noticed i was getting a little warm, so i brought it back to base and bled the cooling system.. it was good after that.. i started it up for another drive about an hour later.. Thats when everything happen...i think its my ECU/tune also, im going to get a OEM ECU see what happens,

SpeedRacer1 - o2 sensor huh? ... whats your reasoning behind that? im interested...

Alright, have you checked all wiring. I mean really check it, check voltages, all grounds, check the continuity of all the wires from the ecm harness back to the plugs. I think there might be a wiring issue, or the ecu. If you have your stock injectors, maf, and ecu. I would swap them back in to see if the problem persists, if it does then you should be able to find the problem relatively easily. If problems end I would say its probably the ecu.

[driftin_sr20det]

Sounds like a good idea. Except if you don't have the stock injectors and maf I wouldn't try running the stock ecu. Thats probably a no brainer but unless its in writing I don't know what your thinking yunno.

[SpeedRacer1]

Nevermind, I was thinking of something else. Who tuned the ECU?