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hey guys im in the process of doing an rb25 conversion.

basically i have got to the stage where i can start the car and with a few throttle pumps it will idle fine but as soon as the engine goes over 1500rpm and the pedal is let off it will stall, it revs up to 4k rpm fine(haven't tried to go higher but it most likely would) but will stall once you back off.

im also getting a little bit of flutter which is strange cause im running the stock BOV, i am using the rb20 crossover pipe and BOV because the rb25 didn't come with one.

i have adjusted the timing with a timing light to 15 degrees.

i have done the majority of the wiring except engine light, water temp, wipers....

the engine was rebuilt 15000ks ago and has been sitting around on a stand for around a year.

i have an exhaust leak between the dump and front pipe due to not having a gasket but i wouldn't expect this to cause the problem i am having

im not %100 on the alignment of the timing belt as i didn't do it.

is there wiring or something i could have missed that would cause this stalling?

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Water temp may be an issue. Some cars (when the wire is not connected) assume the engine is warmed up. If it's not, the ignition timing and fuel will be out until the car does warm up.

*edit: Get the check engine light up. Once you do that you can read the codes and that will tell you what else the computer needs to see*

Edited by BLSTIC
doesnt the RB20 make more boost than the RB25? wouldnt that throw out the stock RB20 BOV and maybe cause flutter?

just an idea..

yeh but it will stall even after revving it to 1500rpm and then backing off, there is no boost at 1500rpm.

i do think it could have something to do with the vacuum/cooler pipe system though.

as for boost control i have welded a nipple into the cooler pipe that comes off the turbo which runs to the boost controller then to the actuator this is correct?

has anyone got a diagram or something of all the piping?

i have a consult display but i haven't got consult wired yet, ill do this and then i can check for errors.

i also have a spare afm i will try, im using an rb20 afm which im told works fine with a S1 r33.

been mucking around with it abit more noticed i don't have the socket end of 6 pin plug circled here i have the 8 pin but only one half of the 6 pin which seems to run back into the main loom... anyone know what its for, ill trace it but im short on time at the moment.

plugmissing.jpg

not my car it will never be so clean!!

tried to get consult working, the thing power's up but cant connect to ecu.

i have a sucking noise coming from the pod on idle i think this is normal but i didn't get it with the rb20.

i get a bit of smoke on idle whiteish blue very fuel-ish smell.

i also fitted up the r33 throttle cable and didn't need any modding like some have described.

Edited by battery

That could be your problem. That part of the loom runs down to the Idle Air Control Valve and knock sensors. You need to separate that plug and wiring from the R33 starter/alternator loom as they are taped together. Im guessing you used the R32 starter/alternator loom so it plugged straight in and thats fine.

That could be your problem. That part of the loom runs down to the Idle Air Control Valve and knock sensors. You need to separate that plug and wiring from the R33 starter/alternator loom as they are taped together. Im guessing you used the R32 starter/alternator loom so it plugged straight in and thats fine.

yeh i used the r32 starter loom, i checked the 33 one for the other end of that plug but its not there, this could be because this side of the loom was modified.

so it defiantly goes into the r33 starter motor loom?

hmm

my 15 year old cousin came over and is like why don't you try the rb20 ECU and i said naa won't do shit but i did it anyway and it works no stalling, timing is way out of course and i won't drive it with the rb20 ecu.

meh i think i might just go get the rb20 ecu remapped and look at some other way of controlling VCT later....

or maybe its possible the r33 ecu i have is stuffed.... don't have access to another one to test though.

i did trace back those wires , 2 of them are for the knock sensors and 3 are ground the last one i can't seem to find.

my 15 year old cousin came over and is like why don't you try the rb20 ECU and i said naa won't do shit but i did it anyway and it works no stalling, timing is way out of course and i won't drive it with the rb20 ecu.

meh i think i might just go get the rb20 ecu remapped and look at some other way of controlling VCT later....

or maybe its possible the r33 ecu i have is stuffed.... don't have access to another one to test though.

i did trace back those wires , 2 of them are for the knock sensors and 3 are ground the last one i can't seem to find.

Hey mate, I think the one you are not able to find is for aux air control valve (blue plug). Also the only difference between 32 & 33 ECU's is 2 injectors

(no. 4 & 6 I think...) are reversed & obviously the lack of VCT. Doing same conversion right now. Good luck...

  • 4 weeks later...
been mucking around with it abit more noticed i don't have the socket end of 6 pin plug circled here i have the 8 pin but only one half of the 6 pin which seems to run back into the main loom... anyone know what its for, ill trace it but im short on time at the moment.

plugmissing.jpg

not my car it will never be so clean!!

tried to get consult working, the thing power's up but cant connect to ecu.

i have a sucking noise coming from the pod on idle i think this is normal but i didn't get it with the rb20.

i get a bit of smoke on idle whiteish blue very fuel-ish smell.

i also fitted up the r33 throttle cable and didn't need any modding like some have described.

the 8 pin plug is for the injector loom, the 6 pin plus is part of the alternator and starter loom on an R33, you NEED to cut the knock sensors out the loom and fit them to your motor, while it wont cure your stall issues, you'll need them to make sure the thing runs safely.

have you cleaned the idle control valve at the back of the manifold? start with this it's possible the solenoid is gummed up a bit. brake cleaner works a treat

the 8 pin plug is for the injector loom, the 6 pin plus is part of the alternator and starter loom on an R33, you NEED to cut the knock sensors out the loom and fit them to your motor, while it wont cure your stall issues, you'll need them to make sure the thing runs safely.

have you cleaned the idle control valve at the back of the manifold? start with this it's possible the solenoid is gummed up a bit. brake cleaner works a treat

yeh sorry guys i did find the solution it was a dud ECU, as far as that plug goes i just used a resistor trick for the knock sensors as the engine doesn't have any installed... i might put them in one day if i can be bothered but im not sure if ill have to remove the plenum to get access..

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