Rb25 running rough looking for ideas to help it out

[Tenchuu]

so just got it installed and running, amn guess is exhaust leak, ony thing is tha ti can't find a big one, just s tiny one on the elbow that can't be fixed due to a drilled out stud, wondering what you guys think:

(dark shitty vid link, who cares about the vid, it is the audio that is concerning)
http://i2.photobucket.com/albums/y19/Tenchuuk/th_DSCN0013.jpg (http://s2.photobucket.com/albums/y19/Tenchuuk/?action=view&current=DSCN0013.flv)


symptoms include:
sounding rough (think V8 with cams)
lack of low end power
(no backfiring)
tiny exh leak between turbo outlet and elbow

mods of any kind:
3" elbow back exhaust
shitty dirty air filter (i still want to know who jacked mine from the garage i was working at)
FMIC
walbro fuel pump
(NISMO FPR going on tomarrow as soon as i can purchase a inline pressure gauge)

ideas that i have had sugestions for include:

accudently put KA 02 sensor on (possibility but would it make a differance?)
air filter too restrictive (i am going to test tha ttheory tomarrow)
MAF problems
CAS not adjusted correctly
that damn leask is makeing the huge differance
undiagnosed problem
it is just running rough get a PFC and tune it out


well i think that about covers most options on this one.

[DriftSpecS14]

hmm.. u check the basics such as injector o rings? if ur dumping lots of fuel into a few cyl it will kill it all. start with the basics and work it up.. a motor is a motor. almost all problms can be cured for diffrent engines with same technique

[kouki_s14]

that leak will killllll it
the leak will leave you with no low end power and sound strange as well. Does it smell like gas in the cabin?

the O2 sensor should be a 3 wire. Koukis use 3 wires as well, so it shouldnt be a problem. If it was incorrect then it wouldnt have even plugged into the harness.

I put my money on the leak, fix it. Any leak is never good, but im pretty sure that will solve your problem.

[chrisman2k]

any ecu codes? I've got a rb25 and I too had a small leak in the DP and it didn't run bad at all, maybe a vac leak or something. Try timing and maf. Also, check the oil cap and dipstick seals. If my car is running and I open one of them, the idle drops and gets a little harsh, and according to a few shops I talked to, that is just something that the rb does. Did you change the plugs? Check the injector o-rings? Compression test before the motor went in? These are all the things I would do, check. Good luck!

[opponheimer]

Make sure your knock sensors are plugged in.

[Tenchuu]

all knock sensors are plugged in, i will check the injectors soon (fucking stock intake manifold makes that a day project with a page of torque specs)
i am hedgeing the bets on the leak too, only thing is that there are 2 ways to fix that leak.
1. replace the turbo or 2. weld elbow to turbo, both of which require tearing the engine back out for a damn exhaust leak, so i am going over everything else first to make sure it isn't something stupid that i am overlooking. and yes i am checking the ECU this morning (should have done it last night)

i will be checking all this stuff thanks for the ideas

[Tenchuu]

OK so i checked the ECU, i got a (21 Ignition circuit) and a (43 Throttle position circuit) guess i know where to start looking now.

[Tenchuu]

problems fixed, the main thing wasn't the exhaust leak

[chrisman2k]

what was it?

[Tenchuu]

damn ECU plug wasn't tight enough..... but the last one i had the ECU bolt broke off in the ECU(as you may already know) so i was Leary about tightening it too much. but i found this out as i was troubleshooting the TPS sensor code thrown by the ECU

i love it when the problem is idiotically simple.

but the FPR is in amd adjusted as well as fan thermo switch now. yay smooth running car.

[chrisman2k]

good to hear!

[MELLO*SOS]

Wow same problem with a Code 21 on my friends KA the other day... The ECU plug wasn't tightened down enough. Glad u got it fixed.

[Tenchuu]

i dig simple to fix problems