R34 Gtst Ecu

[djvoodoo]

Hello fellow sau members

Background: Mods

Turnflow IC

Turbo back zorst

Standard turbs

Standard ECU, injectors, blah blah

Walbro 500hp pump

greddy profec II

About a month or two ago (lets say winter) my ECU has been going into R&R with anything past 7.5psi. My Greddy Pro B is set to lo of 8, hi of 10. (Prior to Winter it was hitting 10psi with no r&r). It's now Spring and temps above 20deg and it's still going r&r

Now I understand what R&R is, I have been to a reputable tuner/mech to check for vacuum/boost/intake leaks/AFM etc etc and understand that the air density in Winter may cause r&r amongst other things

Was wondering if anyone has a spare R34 ECU to do the old switcharoo to see how it reacts to my setup?? Curious to see is all

Located southern Syds

[mad082]

R&R usually gets worse in winter, and isn't as bad in hotter weather. there may possibly be an issue with the AFM, coil packs or spark plugs.

of course swapping in a different ecu will tell you whether it's ecu related however if it still does it it doesn't rule out other possible causes.

what is the actual problem you are having? is it a missfire? if it is then the first thing i would do is check the gap on the plugs if you aren't sure what the gap is, or reduce the gap on the plugs (especially if they are a 1.1mm gap). if that makes the problem go away then you don't have R&R, you have weak coils/spark plugs.

[djvoodoo]

R&R usually gets worse in winter, and isn't as bad in hotter weather. there may possibly be an issue with the AFM, coil packs or spark plugs.

of course swapping in a different ecu will tell you whether it's ecu related however if it still does it it doesn't rule out other possible causes.

what is the actual problem you are having? is it a missfire? if it is then the first thing i would do is check the gap on the plugs if you aren't sure what the gap is, or reduce the gap on the plugs (especially if they are a 1.1mm gap). if that makes the problem go away then you don't have R&R, you have weak coils/spark plugs.

No missfire, I've replaced the sparkies with BCPR6ES .8 gap as well just to be sure. I'll have a good strong pull up until about 4000rpm, then no power till about 5700rpm, then power comes back on to redline. I can also tell in fuel consumption that it's running rich, plus the carbon soot I can see.

Coils seem fine, haven't noticed the common R34 "Slip TCS" light issue that is synonymous with the coilies, but then again, I haven't had a multimeter/voltage test done on them.

Will prob get that and an AFM test done to rule those bits out.

Otherwise it's r&r.. Just gives me an excuse to get an aftermarket ECU really lol.

[mad082]

your best bet would be to put it on a dyno and check the afr's. that will tell you for sure if it's R&R or not. if the power is dipping but afr's aren't changing much then you know it isn't R&R. the fact that it is still doing it in warmer weather makes me think it isn't so much R&R but something else. when i had my 33 i used to only get R&R on very cold mornings and i could always make it do it at certain times of the day in similar temps. on warmer days i couldn't get it to do it at all.

but then it also comes down to whether the R&R is being triggered by a faulty AFM or something like that since it has changed from how it used to be. even things like cleaning the AFM may help with diagnosing the problem.

[djvoodoo]

your best bet would be to put it on a dyno and check the afr's. that will tell you for sure if it's R&R or not. if the power is dipping but afr's aren't changing much then you know it isn't R&R. the fact that it is still doing it in warmer weather makes me think it isn't so much R&R but something else. when i had my 33 i used to only get R&R on very cold mornings and i could always make it do it at certain times of the day in similar temps. on warmer days i couldn't get it to do it at all.

but then it also comes down to whether the R&R is being triggered by a faulty AFM or something like that since it has changed from how it used to be. even things like cleaning the AFM may help with diagnosing the problem.

Yea, you've got some good logical points there. No point in assumptions, may as well get it on the dyno, check the A/FR's, clean AFM etc and then deal with it once I have the results

Cheers mate