PDA

View Full Version : rb25 s2 checking codes


davidg01234
10-24-2012, 02:54 PM
I have a rb25 s2 ecu with out any led light on the ecu. Its in my 90 240sx. So I'm wondering how exactly do I check for codes? I read that you can short the CHK & IGN pins out for 2 seconds and the cel will flash your codes if u have any. But I looked up the pin out for the rb ecu and I'm not seeing and "chk" or "ign" on there! Will somebody please chime in on this for me

davidg01234
10-24-2012, 05:59 PM
Anybody wanna help me out?:ssex:

omgRWDgoodness!
10-24-2012, 06:36 PM
Unfortunately I don't believe there is any way to self-diagnose an RB25DET as the FSM only mentions the use of a Consult :-/ Perhaps try an OBDI scanner? What, if any, issues are you experiencing?

davidg01234
10-24-2012, 06:49 PM
[QUOTE=omgRWDgoodness!;4966048]Unfortunately I don't believe there is any way to self-diagnose an RB25DET as the FSM only mentions the use of a Consult :-/ Perhaps try an OBDI scanner? What, if any, issues are you experiencing?[/QUOT

Hmm I was just reading something about crossing 2 pins on the ecu and the check engine light on the dash will blink your codes. Idk I could very well be wrong. My problems are sputtering and cutting out in the higher rpm range, it mainly happens when the motor is cold. But it'll also do it when its warm too but MAINLY when cold its not just at high rpms though, its just when accelerating period but its worse when in higher rpms. I tried a different maf, changed fuel filter, checked plugs, so the only thing I can think of is the coils. So I just picked up a set of split fires today and will put them on tomorrow and see if that works.

davidg01234
10-24-2012, 06:52 PM
it really sucks not knowing how to pull codes from this ecu because all i can do it take shots in the dark and keep wasting money on things i "think" it might be

omgRWDgoodness!
10-24-2012, 07:05 PM
Check for boost leaks!

davidg01234
10-24-2012, 07:08 PM
Check for boost leaks!


alraedy did it numerous times. i have a pretty good boost leak tester i made :bigok:

but either way if it was a boost leak, it would be sputtering at ALL times not just when it feels like it, correct???

K3MPS
10-24-2012, 07:14 PM
what fuel pump are you running? If its the stock pump it will do that, i experienced it on my SR..

davidg01234
10-24-2012, 07:16 PM
what fuel pump are you running? If its the stock pump it will do that, i experienced it on my SR..

nope no way im runnin stock on an rb, got the 255 which is only about 3 or 4 months old.

K3MPS
10-24-2012, 07:20 PM
sweet, have you checked injectors?

davidg01234
10-24-2012, 07:25 PM
sweet, have you checked injectors?
no i havent checked them. how would i go about doing that? didnt really cross my mind because i have good fuel pressure when idling with and without vacuum on fpr. i dont think its a fuel delivery problem because at times, itll pull hard all the way to redline and i it goes rich as soon as it hits boost like its suppose to (have a wideband) BUT when it feels like sputtering, the wideband shows it going fully lean for a second and then itll jump back to normal

K3MPS
10-24-2012, 07:33 PM
hmmm. Coil packs are probably old/cracked and arcing, change coil packs and report back.

davidg01234
10-24-2012, 07:37 PM
hmmm. Coil packs are probably old/cracked and arcing, change coil packs and report back.

yes this is also what im thinking. one of them has a tiny hairline crack in it. also ive had them covered in water a few times due to rain getting through my vented hood and just puddling up in the valley. not sure if water would hurt them or not but ill be putting on these splits tomorrow and will let yall know how it goes. thanks man alot for your input i highly apreciate you trying to help out

davidg01234
10-25-2012, 02:18 PM
alrighty that was definitely the problem, got the splitfires on, doesnt miss a beat now!:2f2f:

but i would still like to know how to check for codes for future problems