cannot boost

[eci]

dear all sifus...

im running RB25 engine with RB20 wiring+ecu and RB25 injectors with SAFC2.
im expecting this to run rich when boost kicks in at 3000rpm it stutters almost like its runnin lean. im not sure but i hope somebody here can enlighten me about this.

recently i just changed the spark plugs, and i do hope this is the problem.

please help..sos....

 

[weikee]

Something you can try

00) Change your fuel filter
01) Change to higher fuel pump
02) Fuel pressure regulator
03) try to use RB20 injector.. cause your ecu are rb20 ecu.

 

[defcon1]

Have you considered that the RB20 ECU might not be retarding the timing sufficiently when boost kicks in and your engine knocks?

 

[cmng]

very hard to comment since you mention you running SAFC2
need to check what is your SAFC setting as well
but commonly this problem existing when people doing RB25DET conversion using RB20DET wiring and ECU
a lot people end up swaping a RB25DET ECU and wiring to sort it out

 

[eci]

well before putting in SAFC2 the engine runs well with rb20 ecu+wirings, i know that rb25 has extra itc control but since rb20 dun haf..forget it lah...

the idea to put in safc2 is to reduce the damn black smoke coz of rich fuel.

was running fine for 3 months before now...starts to jerk n stutter when boost kicks in.. im going to check the blitz blow off and possible hose leaks now..sigh

 

[a31gtst]

you should seriously consider changing the wiring and ecu. the fuel and ignition maps are different between the 2 engines. you could end up spending alot more money in the long run trying to fix the problem or worst still blow the engine.

Also RB20 injectors are diff from 25 in terms of both feed configuration and impedance. Also check your afm and O2 sensor...sometimes can cause problems...btw first gen rb25 has same afm as the rb20...green sticker.

Best of Luck

 

[eci]

ahh fixed !!
wiring problem to the ecu...all the wiring done one step down..so signal is not so good

now all damn chun...idling cun..thanks all sifu man :_: